Metal tensile laminate

Abstract

To provide a metal-clad laminate that enables the efficient manufacture of wiring circuit boards. [Solution] A metal-clad laminate 1 used in the manufacture of a wiring circuit board 11 by the subtractive method is provided with a metal layer 2 for forming a metal support substrate 12 of the wiring circuit board 11, and a photosensitive resin layer 3 which is a precursor of the first insulating layer 13 of the wiring circuit board 11 and is placed on the metal layer 2.

Description

Technical Field

[0001] The present invention relates to a metal-clad laminate.

Background Art

[0002] Conventionally, a method for manufacturing a substrate for suspension by a subtractive method using a laminate in which a metal substrate, an insulating layer, a seed layer, and a metal plating layer are laminated in this order is known (see, for example, Patent Document 1 below).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the method for manufacturing a wiring circuit board as described in Patent Document 1 above, after a resist for etching is lithographed on the insulating layer, the insulating layer is etched using an etching solution to process the insulating layer, and then the resist for etching is peeled off.

[0005] Therefore, it is difficult to shorten the time required for the lithography work of the resist for etching, the etching process of the insulating layer, and the peeling work of the resist for etching, and it is difficult to improve the manufacturing efficiency.

[0006] The present invention provides a metal-clad laminate that can efficiently manufacture a wiring circuit board.

Means for Solving the Problems

[0007] The present invention [1] includes a metal-clad laminate used in the manufacture of a wiring circuit board by a subtractive method, which does not have a non-photosensitive resin layer, and comprises a metal layer and a photosensitive resin layer which is a precursor of the insulating layer of the wiring circuit board and is disposed on the metal layer.

[0008] The present invention [2] includes the metal-clad laminate of [1], wherein the photosensitive resin layer is disposed on the metal layer via a photosensitive adhesive layer.

[0009] The present invention [3] includes the metal-clad laminate of [1] or [2], further comprising a photosensitive adhesive layer disposed on the photosensitive resin layer.

[0010] The present invention [4] includes the metal-clad laminate of [1] or [2], further comprising a conductive layer disposed on the photosensitive resin layer.

[0011] The present invention [5] includes the metal-clad laminate described in [4], wherein the conductive layer is disposed on the photosensitive resin layer via a photosensitive adhesive layer.

[0012] The present invention [6] includes the metal-clad laminate of [4] or [5] above, wherein the conductive layer is made of copper.

[0013] The present invention [7] includes any one of the above [1] to [6] metal-clad laminates, wherein the metal layer is made of a copper alloy or stainless steel.

[0014] The present invention [8] includes a metal-clad laminate used in the manufacture of a wiring circuit board by subtractive method, which does not have a non-photosensitive resin layer, and comprises a conductor layer and a photosensitive resin layer which is a precursor of the insulating layer of the wiring circuit board and is disposed on the conductor layer.

[0015] The present invention [9] includes the metal-clad laminate of [8], wherein the photosensitive resin layer is disposed on the conductive layer via a photosensitive adhesive layer.

[0016] The present invention

[10] includes the metal-clad laminate of [8] or [9] further having a photosensitive adhesive layer disposed on the photosensitive resin layer.

[0017] The present invention

[11] includes the metal-clad laminate of [8] or [9] further comprising a second conductor layer disposed on the photosensitive resin layer.

[0018] The present invention

[12] includes the metal-clad laminate of

[11] , wherein the second conductor layer is disposed on the photosensitive resin layer via a photosensitive adhesive layer.

[0019] The present invention

[13] includes the metal-clad laminate of

[11] or

[12] , wherein the second conductor layer is made of copper.

[0020] The present invention

[14] includes the metal-clad laminate of any one of [8] to

[13] , wherein the conductor layer is made of copper.

[0021] The present invention

[15] includes the metal-clad laminate of any one of [1] to

[14] , wherein the photosensitive resin layer is made of a photosensitive polyimide.

Advantages of the Invention

[0022] According to the metal-clad laminate of the present invention, by a simple process of exposing and developing the photosensitive resin layer, the photosensitive resin layer can be processed into a predetermined shape, and then, by curing the photosensitive resin layer, an insulating layer having the predetermined shape can be obtained.

[0023] [[ID=3l]]Therefore, the insulating layer can be obtained more efficiently as compared with the case of processing the cured insulating layer.

[0024] As a result, a wiring circuit board can be manufactured more efficiently.

Brief Description of the Drawings

[0025] [Figure 1] FIG. 1 is a cross-sectional view of the metal-clad laminate of the first embodiment. [Figure 2]Figure 2 is a cross-sectional view of a wiring circuit board manufactured using the metal-clad laminate shown in Figure 1. [Figure 3] Figures 3A to 3D are process diagrams of the manufacturing method of a wiring circuit board in the first embodiment, where Figure 3A shows the preparation process, Figure 3B shows the development process, Figure 3C shows the placement process, and Figure 3D shows the etching process. [Figure 4] Figures 4A and 4B, following Figure 3D, are process diagrams of the manufacturing method of a wiring circuit board in the first embodiment, where Figure 4A shows the via formation process and Figure 4B shows the second insulating layer formation process. [Figure 5] Figures 5A to 5C are cross-sectional views showing modified examples of the metal-clad laminate of the first embodiment, where Figure 5A shows the first modified example, Figure 5B shows the second modified example, and Figure 5C shows the third modified example. [Figure 6] Figures 6A to 6D are process diagrams of the manufacturing method of a wiring circuit board in the second embodiment, where Figure 6A shows the preparation process, Figure 6B shows the development process, Figure 6C shows the placement process, and Figure 6D shows the etching process and the second etching process. [Figure 7] Figures 7A and 7B, following Figure 6D, are process diagrams of the manufacturing method of a wiring circuit board in the second embodiment, where Figure 7A shows the via formation process and Figure 7B shows the second insulating layer formation process. [Figure 8] Figures 8A to 8D are process diagrams of the manufacturing method of a wiring circuit board in the third embodiment, where Figure 8A shows the preparation process, Figure 8B shows the placement process, Figure 8C shows the etching process, and Figure 8D shows the development process. [Figure 9] Figures 9A to 9D are process diagrams of the manufacturing method of a wiring circuit board in the fourth embodiment, where Figure 9A shows the preparation step, Figure 9B shows the placement step, Figure 9C shows the etching step and the second etching step, and Figure 9D shows the development step. [Figure 10] Figures 10A and 10B are process diagrams of the manufacturing method of a wiring circuit board in the fifth embodiment, where Figure 10A shows the via formation process and Figure 10B shows the second insulating layer formation process. [Figure 11]Figures 11A to 11F are process diagrams of the manufacturing method of a wiring circuit board in the sixth embodiment, where Figure 11A shows the preparation step, Figure 11B shows the second etching step, Figure 11C shows the step of preparing the conductor layer, Figure 11D shows the etching step, Figure 11E shows the placement step, and Figure 11F shows the development step. [Figure 12] Figure 12 is a cross-sectional view of the metal-clad laminate according to the seventh embodiment. [Figure 13] Figures 13A to 13C are cross-sectional views showing modified examples of the metal-clad laminate of the seventh embodiment, where Figure 13A shows the first modified example, Figure 13B shows the second modified example, and Figure 13C shows the third modified example. [Figure 14] Figure 14 is a cross-sectional view of the metal-clad laminate according to the eighth embodiment. [Figure 15] Figures 15A to 15D are process diagrams of the manufacturing method of a wiring circuit board in the eighth embodiment, where Figure 15A shows the preparation process, Figure 15B shows the development process, Figure 15C shows the etching process, and Figure 15D shows the metal layer bonding process. [Figure 16] Figures 16A to 16C, following Figure 15D, are process diagrams of the manufacturing method of a wiring circuit board in the eighth embodiment, where Figure 16A shows the via formation process, Figure 16B shows the second insulating layer formation process, and Figure 16C shows the second etching process. [Figure 17] Figures 17A to 17C are cross-sectional views showing modified examples of the metal-clad laminate of the eighth embodiment, where Figure 17A shows the first modified example, Figure 17B shows the second modified example, and Figure 17C shows the third modified example. [Figure 18] Figure 18 is a cross-sectional view of the metal-clad laminate according to the ninth embodiment. [Figure 19] Figures 19A to 19D are process diagrams of the manufacturing method of a wiring circuit board in the ninth embodiment, where Figure 19A shows the preparation process, Figure 19B shows the etching process, Figure 19C shows the developing process, and Figure 19D shows the metal layer bonding process. [Figure 20]Figures 20A to 20C, following Figure 19D, are process diagrams of the manufacturing method of a wiring circuit board in the ninth embodiment, where Figure 20A shows the via formation process, Figure 20B shows the second insulating layer formation process, and Figure 20C shows the second etching process. [Figure 21] Figures 21A to 21C are cross-sectional views showing modified examples of the metal-clad laminate of the ninth embodiment, where Figure 21A shows the first modified example, Figure 21B shows the second modified example, and Figure 21C shows the third modified example. [Modes for carrying out the invention]

[0026] 1.Metal-clad laminate The metal-clad laminate 1 of the first embodiment will be described with reference to Figures 1 and 2.

[0027] The metal-clad laminate 1 shown in Figure 1 is used in the manufacture of a wiring circuit board 11 (see Figure 2) using the subtractive method. The metal-clad laminate 1 is traded independently as a material used in the manufacture of the wiring circuit board 11 using the subtractive method. The metal-clad laminate 1 does not include any laminates formed during the manufacturing process of the wiring circuit board 11. The wiring circuit board 11 and the method for manufacturing the wiring circuit board 11 will be described later.

[0028] The metal-clad laminate 1 of this embodiment is a single-sided metal-clad laminate having a metal layer 2 on one surface in the thickness direction. The metal-clad laminate 1 comprises a metal layer 2, a photosensitive resin layer 3, a photosensitive adhesive layer 4, and a protective film 5.

[0029] The metal-clad laminate 1 does not have a non-photosensitive resin layer. A non-photosensitive resin layer is a resin layer that is present during the development process of the manufacturing method of the wiring circuit board 11 described later, and that cannot be patterned by exposure and development. Examples of non-photosensitive resin layers include the insulating layer of a copper-clad laminate and the insulating layer of a wiring circuit board. The protective film 5 is peeled off during the preparation process of the manufacturing method of the wiring circuit board 11 described later, and therefore is not present during the development process. For this reason, the protective film 5 is not included in the non-photosensitive resin layer.

[0030] (1) Metal layer The metal layer 2 is a layer for forming the metal support substrate 12 (see Figure 2) of the wiring circuit board 11.

[0031] The material of the metal layer 2 is not limited as long as it can provide the required rigidity for the metal support substrate 12. Examples of materials for the metal layer 2 include copper alloy, stainless steel, copper, 42 alloy, and Monel. Preferably, the metal layer 2 is made of a copper alloy or stainless steel.

[0032] The thickness of the metal layer 2 is not limited as long as it can provide the required rigidity for the metal support substrate 12. The thickness of the metal layer 2 is, for example, 1 μm or more and, for example, 250 μm or less.

[0033] (2) Photosensitive resin layer The photosensitive resin layer 3 is a precursor to the first insulating layer 13 (see Figure 2), which is an example of an insulating layer for the wiring circuit board 11. The photosensitive resin layer 3 is positioned on top of the metal layer 2 in the thickness direction of the metal-clad laminate 1.

[0034] The photosensitive resin layer 3 can be patterned by exposure and development. Examples of materials for the photosensitive resin layer 3 include photosensitive polyimide, photosensitive epoxy resin, and photosensitive polybenzoxazole.

[0035] The photosensitive resin layer 3 is preferably made of a photosensitive polyimide. The photosensitive polyimide contains, for example, a polyamic acid (uncured polyimide) having a photoreactive functional group. The photosensitive polyimide may also contain a polyamic acid and a photosensitive agent.

[0036] The photosensitive resin layer 3 is patterned by exposure and development, and then cured by heating as necessary. The photosensitive resin layer 3 may be a negative type in which the exposed portion becomes insoluble in the developer, or a positive type in which the exposed portion dissolves in the developer. Preferably, the photosensitive resin layer 3 is a negative type.

[0037] The thickness of the photosensitive resin layer 3 is, for example, 1 μm or more, and for example, 50 μm or less.

[0038] (3) Photosensitive adhesive layer The photosensitive adhesive layer 4 is positioned on top of the photosensitive resin layer 3 in the thickness direction of the metal-clad laminate 1. The photosensitive adhesive layer 4 can be patterned together with the photosensitive resin layer 3 by exposure and development. In other words, if the photosensitive resin layer 3 is negative type, the photosensitive adhesive layer 4 is also negative type, and if the photosensitive resin layer 3 is positive type, the photosensitive adhesive layer 4 is also positive type.

[0039] After the photosensitive adhesive layer 4 is exposed to light and developed, but before the photosensitive adhesive layer 4 is fully cured, the photosensitive adhesive layer 4 has stronger adhesive strength than the photosensitive resin layer 3. The photosensitive adhesive layer 4 may have adhesive strength both before exposure and development, and after exposure and development. In the arrangement step of the manufacturing method of the wiring circuit board 11 described later (see Figure 3C), the photosensitive adhesive layer 4 adheres the photosensitive resin layer 3 and the conductor layer 140.

[0040] The photosensitive adhesive layer 4 may contain, for example, an uncured thermosetting resin having photoreactive functional groups. The photosensitive adhesive layer 4 may contain an uncured thermosetting resin and a photosensitive agent. The photosensitive adhesive layer 4 may contain a thermoplastic resin having photoreactive functional groups. The photosensitive adhesive layer 4 may contain a thermoplastic resin and a photosensitive agent.

[0041] Examples of materials for the photosensitive adhesive layer 4 include photosensitive thermosetting resins and photosensitive thermoplastic resins. Examples of photosensitive thermosetting resins include photosensitive epoxy resins, photosensitive polyimides, and photosensitive urethane resins. Examples of photosensitive thermoplastic resins include photosensitive acrylic resins.

[0042] Examples of negative-type photosensitive epoxy resins used as the photosensitive adhesive layer 4 include biphenyl-type epoxy resin (uncured thermosetting resin) and a mixture of bisphenol F-type epoxy resin (uncured thermosetting resin) and 4,4-bis[di(β-hydroxyethoxy)phenylsulfinio]phenylsulfidebis(hexafluoroantimonate) (photosensitive agent).

[0043] Examples of negative-type photosensitive polyimides used as the photosensitive adhesive layer 4 include a mixture of a reaction product (polyamic acid) of ethylene glycol bis-trimellitic dianhydride (acidic dianhydride component), 1,12-diaminodecane (diamine component), and 1,3-bis-(3-aminopropyl)tetramethyldisiloxane (diamine component), and 1-ethyl-3,5-dimethoxycarbonyl-4-(2-nitrophenyl)-1,4-dihydropyridine (photosensitive agent).

[0044] The photosensitive adhesive layer 4 is thinner than the photosensitive resin layer 3. The photosensitive adhesive layer 4 may have the same thickness as the photosensitive resin layer 3. The thickness of the photosensitive adhesive layer 4 is, for example, 1x or less of the thickness of the photosensitive resin layer 3, preferably 1 / 2 or less, and for example, 1 / 3 or more. The thickness of the photosensitive adhesive layer 4 is, for example, 1 μm or more, and for example, 25 μm or less.

[0045] (4) Protective film The protective film 5 protects the photosensitive resin layer 3 and the photosensitive adhesive layer 4. The protective film 5 is positioned on the photosensitive adhesive layer 4 in the thickness direction of the metal-clad laminate 1. The protective film 5 covers the photosensitive resin layer 3 and the photosensitive adhesive layer 4. The protective film 5 is peelable from the photosensitive adhesive layer 4.

[0046] 2. Method for manufacturing metal-clad laminates To manufacture the metal-clad laminate 1, first, a photosensitive resin layer 3 is formed on the metal layer 2.

[0047] To form the photosensitive resin layer 3, for example, a solution of photosensitive resin (varnish) is applied to the metal layer 2 and dried. This forms the photosensitive resin layer 3 on the metal layer 2.

[0048] Next, a photosensitive adhesive layer 4 is formed on the photosensitive resin layer 3.

[0049] To form the photosensitive adhesive layer 4, for example, a solution of the photosensitive adhesive (varnish) is applied to the photosensitive resin layer 3 and dried. This forms the photosensitive adhesive layer 4 on the photosensitive resin layer 3.

[0050] Next, a protective film 5 is bonded onto the photosensitive adhesive layer 4. This completes the process of obtaining the metal-clad laminate 1.

[0051] In addition, to manufacture the metal-clad laminate 1, a photosensitive adhesive layer 4 and a photosensitive resin layer 3 may be formed sequentially on the protective film 5, and then the metal layer 2 may be bonded to the photosensitive resin layer 3.

[0052] 3. Wiring circuit board Next, with reference to Figure 2, a wiring circuit board 11 manufactured using the metal-clad laminate 1 will be described.

[0053] The wiring circuit board 11 comprises a metal support substrate 12, a first insulating layer 13 as an example of an insulating layer, a conductor pattern 14, vias 15, and a second insulating layer 16. The wiring circuit board 11 does not necessarily have to include vias 15.

[0054] (1) Metal support substrate The metal support substrate 12 supports the first insulating layer 13, the conductor pattern 14, the vias 15, and the second insulating layer 16. In this embodiment, the metal support substrate 12 is formed from the metal layer 2 (see Figure 1) of the metal-clad laminate 1.

[0055] (2) First insulating layer The first insulating layer 13 is placed on the metal support substrate 12 in the thickness direction of the wiring circuit board 11. The first insulating layer 13 is placed between the metal support substrate 12 and the conductor pattern 14. The first insulating layer 13 insulates the metal support substrate 12 from the conductor pattern 14. The first insulating layer 13 is provided in the portion where the conductor pattern 14 is formed. The first insulating layer 13 is a cured product of the photosensitive resin layer 3 (see Figure 1) of the metal-clad laminate 1.

[0056] (3) Conductor pattern The conductor pattern 14 is positioned on the first insulating layer 13 in the thickness direction of the wiring circuit board 11. The conductor pattern 14 is positioned on the first insulating layer 13 in the thickness direction of the wiring circuit board 11 via a bonding layer 17, which is a cured product of the photosensitive adhesive layer 4. The bonding layer 17 bonds the first insulating layer 13 and the conductor pattern 14.

[0057] The conductor pattern 14 is made of metal. Examples of metals include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. From the viewpoint of obtaining good electrical properties, copper is preferred.

[0058] The shape of the conductor pattern 14 is not limited. In this embodiment, the conductor pattern 14 has a plurality of independent wiring patterns 14A, 14B, 14C, and 14D.

[0059] (4) Beer The via 15 penetrates the wiring pattern 14D, the bonding layer 17, and the first insulating layer 13 in the thickness direction of the wiring circuit board 11. The via 15 electrically connects the wiring pattern 14D and the metal support substrate 12.

[0060] (5) Second insulating layer The second insulating layer 16 covers the conductor pattern 14 and via 15. The second insulating layer 16 is positioned on top of the bonding layer 17 in the thickness direction of the wiring circuit board 11. The second insulating layer 16 is made of a thermosetting resin. Examples of thermosetting resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester.

[0061] 4. Manufacturing method of a wiring circuit board Next, the manufacturing method of the wiring circuit board 11 will be described with reference to Figures 2 to 4B.

[0062] The method for manufacturing a wiring circuit board includes a preparation step (see Figure 3A), a development step (see Figure 3B), a placement step (see Figure 3C), an etching step (see Figure 3D), a via formation step (see Figure 4A), a second insulating layer formation step (see Figure 4B), and a second etching step (see Figures 4B and 2). In this embodiment, the steps are performed in the order of preparation, development, placement, etching, second insulating layer formation, and second etching. That is, the placement step is performed after the development step, and the etching step is performed after the placement step.

[0063] (1) Preparation process As shown in Figure 3A, in the preparation step, the metal-clad laminate 1 described above is prepared and the protective film 5 (see Figure 1) is peeled off. In this embodiment, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are negative type.

[0064] (2)Developing process Next, as shown in Figure 3B, the developing process involves exposing and developing the photosensitive resin layer 3 and the photosensitive adhesive layer 4. This patterns the photosensitive resin layer 3 and the photosensitive adhesive layer 4 into the desired shape.

[0065] In the development process, first, a portion of the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are exposed via a photoresist. As a result, the exposed portion of the photosensitive resin layer 3 and the photosensitive adhesive layer 4 becomes insoluble in the developer solution.

[0066] Next, the exposed photosensitive resin layer 3 and photosensitive adhesive layer 4 are immersed in a developer solution. The unexposed portions of the photosensitive resin layer 3 and photosensitive adhesive layer 4 dissolve and are removed by the developer solution. The exposed portions of the photosensitive resin layer 3 and photosensitive adhesive layer 4 remain without dissolving in the developer solution. This allows the photosensitive resin layer 3 and photosensitive adhesive layer 4 to be developed in the desired pattern.

[0067] Note that the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are in an uncured state after the development process.

[0068] (3) Placement process Next, as shown in Figure 3C, in the placement process, the conductive layer 140 is placed on top of the photosensitive resin layer 3.

[0069] In more detail, during the placement process, a conductive layer 140 made of metal foil is bonded onto the photosensitive adhesive layer 4.

[0070] The conductive layer 140 is a layer for forming the conductive pattern 14. The conductive layer 140 is made of a metal. Examples of metals include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. From the viewpoint of obtaining good electrical properties, the conductive layer 140 is preferably made of copper.

[0071] The conductive layer 140 is thinner than the metal layer 2. The thickness of the conductive layer 140 is, for example, 1 μm or more and, for example, 50 μm or less.

[0072] The conductive layer 140 is placed on top of the photosensitive resin layer 3 via the photosensitive adhesive layer 4. The conductive layer 140 is bonded to the photosensitive resin layer 3 via the photosensitive adhesive layer 4.

[0073] Subsequently, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are heated and cured as necessary. This forms the first insulating layer 13, which is the cured photosensitive resin layer 3, and the bonding layer 17, which is the cured photosensitive adhesive layer 4.

[0074] (4) Etching process Next, as shown in Figure 3D, in the etching process, a portion of the conductive layer 140 is etched to form a conductive pattern 14.

[0075] In the etching process, first, a dry film resist is applied to the conductive layer 140.

[0076] Next, the dry film resist is exposed and developed to form an etching resist. The etching resist covers the portion of the conductive layer 140 that will become the conductive pattern 14.

[0077] Next, the portion of the conductive layer 140 that is exposed from the etching resist is etched with an etching solution.

[0078] As a result, the portion of the conductive layer 140 that is exposed from the etching resist is removed, and the conductive pattern 14 is formed.

[0079] (5) Via formation process Next, as shown in Figure 4A, via 15 is formed in the via formation process.

[0080] To form the via 15, for example, a via hole 15A that penetrates the wiring pattern 14D, the bonding layer 17, and the first insulating layer 13 is formed by laser etching.

[0081] Next, vias 15 are formed in via holes 15A by electrolytic plating or electroless plating.

[0082] (6) Second insulating layer formation process Next, as shown in Figure 4B, in the second insulating layer formation step, the second insulating layer 16 is formed.

[0083] To form the second insulating layer 16, first, a dry film of the material for the second insulating layer described above is attached to the bonding layer 17 so as to cover the conductor pattern 14.

[0084] Next, the dry film is exposed to light and developed, and heated and cured as necessary to form the second insulating layer 16.

[0085] (7) Second etching process Next, as shown in Figures 4B and 2, in the second etching step, a portion of the metal layer 2 is etched to form the metal support substrate 12.

[0086] More specifically, in the second etching process, a dry film resist is first applied to the metal layer 2.

[0087] Next, the dry film resist is exposed and developed to form an etching resist. The etching resist covers the portion of the metal layer 2 that will become the metal support substrate 12.

[0088] Next, the portion of metal layer 2 exposed from the etching resist is etched with an etching solution.

[0089] As a result, the portion of the metal layer 2 exposed from the etching resist is removed, and the metal support substrate 12 is formed.

[0090] With the above steps completed, the manufacturing of the wiring circuit board 11 is finished, and the wiring circuit board 11 is obtained as shown in Figure 2.

[0091] 5. Effects According to the metal-clad laminate 1, as shown in Figures 3A and 3B, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 can be processed into a predetermined shape by a simple process of exposure and development of the photosensitive resin layer 3 and the photosensitive adhesive layer 4. Then, as shown in Figures 3C and 3D, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 can be cured to obtain a first insulating layer 13 and a bonding layer 17 of a predetermined shape.

[0092] Therefore, compared to processing a hardened insulating layer, the first insulating layer 13 can be obtained more efficiently.

[0093] As a result, the wiring circuit board 11 can be manufactured efficiently.

[0094] 6. Modified examples of metal-clad laminates A modified example of the metal-clad laminate 1 will be described with reference to Figures 5A to 5C. In the modified example of the metal-clad laminate 1, components similar to those in the first embodiment are denoted by the same reference numerals, and their descriptions are omitted.

[0095] (1) As shown in Figure 5A, the metal-clad laminate 1 does not necessarily have a photosensitive adhesive layer 4. In this case, the metal-clad laminate 1 comprises, in the thickness direction, a metal layer 2, a photosensitive resin layer 3, and a protective film 5 in that order. The photosensitive resin layer 3 has adhesive properties after exposure and development, but before curing is complete. The protective film 5 is placed on top of the photosensitive resin layer 3. Also, in the arrangement step of the manufacturing method of the wiring circuit board 11 (see Figure 3C), the conductor layer 140 is directly bonded to the photosensitive resin layer 3.

[0096] (2) As shown in Figure 5B, the metal-clad laminate 1 may not have a photosensitive adhesive layer 4, but may have a photosensitive adhesive layer 6 between the metal layer 2 and the photosensitive resin layer 3. In other words, the photosensitive resin layer 3 may be placed on the metal layer 2 via the photosensitive adhesive layer 6. In this case, the metal-clad laminate 1 comprises, in the thickness direction, the metal layer 2, the photosensitive adhesive layer 6, the photosensitive resin layer 3, and the protective film 5 in that order. In the developing step of the manufacturing method of the wiring circuit board 11 (see Figure 3B), the photosensitive adhesive layer 6 is exposed and developed together with the photosensitive resin layer 3 and patterned into a desired shape. Thereafter, the photosensitive adhesive layer 6 hardens to form a bonding layer that joins the metal support substrate 12 (see Figure 2) and the first insulating layer 13 (see Figure 2).

[0097] (3) As shown in Figure 5C, the metal-clad laminate 1 may be provided with, in the thickness direction, a metal layer 2, a photosensitive adhesive layer 6, a photosensitive resin layer 3, a photosensitive adhesive layer 4, and a protective film 5 in that order.

[0098] (4) The same effects and advantages as in the first embodiment can be obtained with the metal-clad laminate 1 of the modified examples (1) to (3).

[0099] 7. Second Embodiment Next, a second embodiment will be described with reference to Figures 6A to 7B. In the second embodiment, the same steps as in the first embodiment will not be described.

[0100] In the second embodiment, the processes are carried out in the following order: preparation (see Figure 6A), development (see Figure 6B), placement (see Figure 6C), etching and second etching (see Figure 6D), via formation (see Figure 7A), and second insulating layer formation (see Figure 7B). In the second embodiment, as shown in Figure 6D, the etching process and the second etching process are carried out simultaneously to form the metal support substrate 12 and the conductor pattern 14 at the same time. This shortens the manufacturing process of the wiring circuit board 11 compared to the case where the metal support substrate 12 and the conductor pattern 14 are formed in separate processes.

[0101] In the second embodiment, the same effects and advantages as in the first embodiment can be obtained.

[0102] 8. Third Embodiment Next, a third embodiment will be described with reference to Figures 8A to 8D, 4A, 4B, and 2. In the third embodiment, the same steps as in the first embodiment will not be described.

[0103] In the third embodiment, the following steps are performed in order: preparation step (see Figure 8A), placement step (see Figure 8B), etching step (see Figure 8C), developing step (see Figure 8D), via formation step (see Figure 4A), second insulating layer formation step (see Figure 4B), and second etching step (see Figures 4B and 2). In other words, in the third embodiment, the etching step is performed after the placement step, and the developing step is performed after the etching step.

[0104] In the third embodiment, as shown in Figure 8D, in the development process, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are exposed to light and developed, and then heated as necessary to cure them.

[0105] In the third embodiment, the same effects and advantages as in the first embodiment can be obtained.

[0106] 9. Fourth Embodiment Next, the fourth embodiment will be described with reference to Figures 9A to 9D, 4A, and 4B. In the fourth embodiment, the same steps as in the first embodiment will not be described.

[0107] In the fourth embodiment, the following steps are performed in order: preparation step (see Figure 9A), placement step (see Figure 9B), etching step and second etching step (see Figure 9C), developing step (see Figure 9D), via formation step (see Figure 4A), and second insulating layer formation step (see Figure 4B).

[0108] In the fourth embodiment, as shown in Figure 9C, the etching process and the second etching process are performed simultaneously to form the metal support substrate 12 and the conductor pattern 14 at the same time. This shortens the manufacturing process of the wiring circuit board 11 compared to the case where the metal support substrate 12 and the conductor pattern 14 are formed in separate processes.

[0109] In the fourth embodiment, the same effects and advantages as in the first embodiment can be obtained.

[0110] 10. Fifth Embodiment Next, the fifth embodiment will be described with reference to Figures 9A to 9C, 10A, 10B, and 2. In the fifth embodiment, the same steps as in the fourth embodiment will not be described.

[0111] In the fifth embodiment, the following steps are performed in order: preparation step (see Figure 9A), placement step (see Figure 9B), etching step and second etching step (see Figure 9C), via formation step (see Figure 10A), second insulating layer formation step (see Figure 10B), and development step (see Figures 10B and 2).

[0112] In the fifth embodiment, as shown in Figure 10A, during the via formation process, via holes 15A are formed that penetrate the wiring pattern 14D, the photosensitive adhesive layer 4 before exposure, and the photosensitive resin layer 3 before exposure, and vias 15 are formed within the via holes 15A.

[0113] Furthermore, in the fifth embodiment, as shown in Figure 10B, in the second insulating layer formation step, the second insulating layer 16 is formed on the photosensitive adhesive layer 4 before exposure.

[0114] Furthermore, in the fifth embodiment, as shown in Figures 10B and 2, in the development process, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are exposed to light and developed, and then heated as necessary to cure them.

[0115] In the fifth embodiment, the same effects and advantages as in the fourth embodiment can be obtained.

[0116] 11. Sixth Embodiment Next, the sixth embodiment will be described with reference to Figures 11A to 11F, 7A, and 7B. In the sixth embodiment, the same steps as in the first embodiment will not be described.

[0117] In the sixth embodiment, first, a preparation step (see Figure 11A) and a second etching step (see Figure 11B) are performed.

[0118] In addition, separate from the preparation step and the second etching step, as shown in Figures 11C and 11D, before placing the conductive layer 140 on the photosensitive adhesive layer 4, a portion of the conductive layer 140 is etched to form a conductive pattern 14 (etching step).

[0119] Next, as shown in Figure 11E, the conductor pattern 14 is placed on the photosensitive adhesive layer 4 (placement step). In other words, in the sixth embodiment, the placement step is performed after the etching step.

[0120] Next, as shown in Figure 11F, the development process is performed. In other words, in the sixth embodiment, the development process is performed after the placement process.

[0121] Subsequently, the via formation process (see Figure 7A) and the second insulating layer formation process (see Figure 7B) are performed.

[0122] In the sixth embodiment, the same effects and advantages as in the first embodiment can be obtained.

[0123] In the sixth embodiment, instead of placing the conductor pattern 14 in the placement step, a wiring circuit board having the conductor pattern 14 can also be placed on the photosensitive adhesive layer 4.

[0124] 12. Seventh Embodiment Next, the seventh embodiment will be described with reference to Figures 12, 8B to 8D, 4A, 4B, 2, 9B to 9D, 10A, 10B, and 13A to 13C. In the seventh embodiment, the same reference numerals are used for components as in the first embodiment, and their descriptions are omitted.

[0125] As shown in Figure 12, the metal-clad laminate 100 of the seventh embodiment is a double-sided metal-clad laminate having a metal layer 2 on one surface in the thickness direction and a conductive layer 140 on the other surface in the thickness direction. In the seventh embodiment, the metal-clad laminate 100 comprises, in the thickness direction, a metal layer 2, a photosensitive resin layer 3, a photosensitive adhesive layer 4, and a conductive layer 140 in that order. The conductive layer 140 is disposed on the photosensitive resin layer 3 via the photosensitive adhesive layer 4.

[0126] In the seventh embodiment, the assembly step is unnecessary in the manufacturing method of the wiring circuit board 11. That is, in the manufacturing method of the wiring circuit board 11, for example, the steps are performed in the following order: preparation step (see Figure 8B), etching step (see Figure 8C), developing step (see Figure 8D), via formation step (see Figure 4A), second insulating layer formation step (see Figure 4B), and second etching step (see Figures 4B and 2).

[0127] In the seventh embodiment, the manufacturing method for the wiring circuit board 11 may be carried out in the following order: preparation step (see Figure 9B), etching step and second etching step (see Figure 9C), developing step (see Figure 9D), via formation step (see Figure 4A), and second insulating layer formation step (see Figure 4B).

[0128] Furthermore, in the seventh embodiment, the manufacturing method of the wiring circuit board 11 may be carried out in the following order: preparation step (see Figure 9B), etching step and second etching step (see Figure 9C), via formation step (see Figure 10A), second insulating layer formation step (see Figure 10B), and developing step (see Figures 10B and 2).

[0129] Furthermore, as shown in Figure 13A, the metal-clad laminate 100 of the seventh embodiment does not need to have a photosensitive adhesive layer 4.

[0130] Furthermore, as shown in Figure 13B, the metal-clad laminate 100 of the seventh embodiment may not have a photosensitive adhesive layer 4, but may have a photosensitive adhesive layer 6 between the metal layer 2 and the photosensitive resin layer 3.

[0131] Furthermore, as shown in Figure 13C, the metal-clad laminate 100 of the seventh embodiment may comprise, in the thickness direction, a metal layer 2, a photosensitive adhesive layer 6, a photosensitive resin layer 3, a photosensitive adhesive layer 4, and a conductive layer 140 in that order.

[0132] In the seventh embodiment, the same effects and advantages as in the first embodiment can be obtained.

[0133] 13. Eighth Embodiment Next, the eighth embodiment will be described with reference to Figures 14 to 17C. In the eighth embodiment, the same reference numerals are used for components similar to those in the first embodiment, and their descriptions are omitted.

[0134] As shown in Figure 14, the metal-clad laminate 200 of the eighth embodiment is a single-sided metal-clad laminate having a conductive layer 140 on one surface in the thickness direction. In the eighth embodiment, the metal-clad laminate 200 comprises, in the thickness direction, a conductive layer 140, a photosensitive adhesive layer 4, a photosensitive resin layer 3, and a protective film 5 in that order. In the eighth embodiment, the photosensitive resin layer 3 is disposed on the conductive layer 140 via the photosensitive adhesive layer 4.

[0135] In the eighth embodiment, the manufacturing method for the wiring circuit board 11 is performed in the following order, for example: preparation step (see Figure 15A), development step (see Figure 15B), etching step (see Figure 15C), metal layer bonding step (see Figure 15D), via formation step (see Figure 16A), second insulating layer formation step (see Figure 16B), and second etching step (see Figures 16B and 16C).

[0136] As shown in Figure 15A, the preparation step involves preparing the metal-clad laminate 200 (see Figure 14) described above.

[0137] As shown in Figure 15B, in the developing process, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are exposed to light, developed, and cured.

[0138] As shown in Figure 15C, in the etching process, a portion of the conductive layer 140 is etched to form a conductive pattern 14.

[0139] As shown in Figure 15D, in the metal layer bonding process, the metal layer 2 is bonded to the other side of the first insulating layer 13 in the thickness direction via an adhesive layer 201.

[0140] As shown in Figure 16A, in the via formation process, via holes 15A are formed that penetrate the wiring pattern 14D, the bonding layer 17, the first insulating layer 13, and the adhesive layer 201, and vias 15 are formed within the via holes 15A.

[0141] As shown in Figure 16B, in the second insulating layer formation step, the second insulating layer 16 is formed on the bonding layer 17 so as to cover the conductor pattern 14.

[0142] As shown in Figures 16B and 16C, in the second etching step, a portion of the metal layer 2 is etched to form the metal support substrate 12.

[0143] In the eighth embodiment, the manufacturing method for the wiring circuit board 11 may be performed in the following order, for example: preparation step (see Figure 15A), etching step (see Figure 15C), developing step (see Figure 15B), metal layer bonding step (see Figure 15D), via formation step (see Figure 16A), second insulating layer formation step (see Figure 16B), and second etching step (see Figures 16B and 16C).

[0144] Furthermore, in the eighth embodiment, in the method for manufacturing the wiring circuit board 11, for example, first a preparation step (see Figure 15A), a developing step (see Figure 15B), and an etching step (see Figure 15C) may be performed, and separately, a part of the metal layer 2 may be etched to form a metal support substrate 12 (second etching step), and then the metal support substrate 12 may be bonded to the first insulating layer 13 via an adhesive layer 201 (metal layer bonding step).

[0145] Furthermore, as shown in Figure 17A, the metal-clad laminate 200 does not necessarily have a photosensitive adhesive layer 4. In this case, the metal-clad laminate 200 comprises, in the thickness direction, a conductive layer 140, a photosensitive resin layer 3, and a protective film 5 in that order. The photosensitive resin layer 3 has adhesive strength after exposure and development, but before curing is complete. In the metal layer bonding step of the manufacturing method of the wiring circuit board 11 (see Figure 15D), the metal layer 2 is directly bonded to the photosensitive resin layer 3.

[0146] Furthermore, as shown in Figure 17B, the metal-clad laminate 200 may not have a photosensitive adhesive layer 4, but may have a photosensitive adhesive layer 6. The photosensitive adhesive layer 6 is placed on top of the photosensitive resin layer 3. In this case, the metal-clad laminate 200 comprises, in the thickness direction, a conductor layer 140, a photosensitive resin layer 3, a photosensitive adhesive layer 6, and a protective film 5 in that order. In the metal layer bonding step of the manufacturing method of the wiring circuit board 11 (see Figure 15D), the metal layer 2 is bonded to the photosensitive resin layer 3 by the photosensitive adhesive layer 6. In other words, the adhesive layer 201 is unnecessary in the metal layer bonding step of the manufacturing method of the wiring circuit board 11 (see Figure 15D).

[0147] Furthermore, as shown in Figure 17C, the metal-clad laminate 200 may also comprise, in the thickness direction, a conductive layer 140, a photosensitive adhesive layer 4, a photosensitive resin layer 3, a photosensitive adhesive layer 6, and a protective film 5 in that order.

[0148] In the eighth embodiment, the same effects and advantages as in the first embodiment can be obtained.

[0149] 14. Ninth Embodiment Next, the eighth embodiment will be described with reference to Figures 18 to 21C. In the eighth embodiment, the same reference numerals are used for components as in the first embodiment, and their descriptions are omitted.

[0150] As shown in Figure 18, the metal-clad laminate 300 of the ninth embodiment is a double-sided metal-clad laminate having a conductive layer 140 on one surface in the thickness direction and a second conductive layer 301 on the other surface in the thickness direction. In the ninth embodiment, the metal-clad laminate 300 comprises, in the thickness direction, a conductive layer 140, a photosensitive adhesive layer 4, a photosensitive resin layer 3, and a second conductive layer 301 in that order.

[0151] The second conductor layer 301 is placed on top of the photosensitive resin layer 3. The second conductor layer 301 is a layer for forming the second conductor pattern 302. The second conductor pattern 302 is placed on the opposite side of the wiring patterns 14A, 14B, 14C, and 14D from the first insulating layer 13 (see Figure 20C) in order to reduce the transmission loss of the wiring patterns 14A, 14B, 14C, and 14D (see Figure 20C).

[0152] The second conductor layer 301 is made of a metal. Examples of metals include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. From the viewpoint of obtaining good electrical properties, the second conductor layer 301 is preferably made of copper.

[0153] The thickness of the second conductor layer 301 is, for example, 1 μm or more and, for example, 50 μm or less.

[0154] In the ninth embodiment, the manufacturing method for the wiring circuit board 11 is performed in the following order, for example: preparation step (see Figure 19A), etching step (see Figure 19B), developing step (see Figure 19C), metal layer bonding step (see Figure 19D), via formation step (see Figure 20A), second insulating layer formation step (see Figure 20B), and second etching step (see Figures 20B and 20C).

[0155] As shown in Figure 19A, the preparation step involves preparing the metal-clad laminate 300 (see Figure 18) described above.

[0156] As shown in Figure 19B, in the etching process, a portion of the conductor layer 140 is etched to form a conductor pattern 14, and a portion of the second conductor layer 301 is etched to form a second conductor pattern 302.

[0157] As shown in Figure 19C, in the development process, the photosensitive resin layer 3 and the photosensitive adhesive layer 4 are exposed to light, developed, and cured.

[0158] As shown in Figure 19D, in the metal layer bonding process, the metal layer 2 is bonded to the second conductor pattern 302 via the adhesive layer 201.

[0159] As shown in Figure 20A, in the via formation process, via holes 15A are formed that penetrate the wiring pattern 14D, the bonding layer 17, the first insulating layer 13, the second conductor pattern 302, and the adhesive layer 201, and vias 15 are formed within the via holes 15A.

[0160] As shown in Figure 20B, in the second insulating layer formation step, the second insulating layer 16 is formed on the bonding layer 17 so as to cover the conductor pattern 14.

[0161] As shown in Figures 20B and 20C, in the second etching step, a portion of the metal layer 2 is etched to form the metal support substrate 12.

[0162] As shown in Figure 21A, the metal-clad laminate 300 does not necessarily have a photosensitive adhesive layer 4. In this case, the metal-clad laminate 300 comprises, in the thickness direction, a conductor layer 140, a photosensitive resin layer 3, and a second conductor layer 301 in that order.

[0163] Furthermore, as shown in Figure 21B, the metal-clad laminate 300 may not have a photosensitive adhesive layer 4, but may have a photosensitive adhesive layer 303. The photosensitive adhesive layer 303 is placed between the photosensitive resin layer 3 and the second conductor layer 301. In other words, the second conductor layer 301 is placed on top of the photosensitive resin layer 3 via the photosensitive adhesive layer 303. In this case, the metal-clad laminate 300 comprises, in the thickness direction, the conductor layer 140, the photosensitive resin layer 3, the photosensitive adhesive layer 303, and the second conductor layer 301 in that order.

[0164] Furthermore, as shown in Figure 21C, the metal-clad laminate 300 may also comprise, in the thickness direction, a conductor layer 140, a photosensitive adhesive layer 4, a photosensitive resin layer 3, a photosensitive adhesive layer 303, and a second conductor layer 301 in that order.

[0165] In the ninth embodiment, the same effects and advantages as in the first embodiment can be obtained. [Explanation of Symbols]

[0166] 1 Metal-clad laminate 2 metal layers 3 Photosensitive resin layer 4 Photosensitive adhesive layer 6 Photosensitive adhesive layer 11 Wiring circuit board 12 Metal support substrate 13. First insulating layer (an example of an insulating layer) 14 Conductor Patterns 140 Conductor layer 100 Metal clad laminate 200 Metal clad laminate 300 Metal clad laminate 301 Second Conductor Layer 302 Second Conductor Pattern 303 Photosensitive adhesive layer

Claims

1. A metal-clad laminate used in the manufacture of wiring circuit boards by the subtractive method, Without a non-photosensitive resin layer, A metal layer for forming the metal support substrate of the aforementioned wiring circuit board, A precursor to the insulating layer of the wiring circuit board, and a photosensitive resin layer disposed on the metal layer. A metal-clad laminate equipped with the following features.

2. The metal-clad laminate according to claim 1, wherein the photosensitive resin layer is disposed on the metal layer via a photosensitive adhesive layer.

3. The metal-clad laminate according to claim 1 or 2, further comprising a photosensitive adhesive layer disposed on the photosensitive resin layer.

4. The metal-clad laminate according to claim 1 or 2, further comprising a conductive layer disposed on the photosensitive resin layer for forming a conductive pattern of the wiring circuit board.

5. The metal-clad laminate according to claim 4, wherein the conductive layer is disposed on the photosensitive resin layer via a photosensitive adhesive layer.

6. The metal-clad laminate according to claim 4 or 5, wherein the conductive layer is made of copper.

7. The metal layer is made of a copper alloy or stainless steel, as described in any one of claims 1 to 6.

8. A metal-clad laminate used in the manufacture of wiring circuit boards by the subtractive method, Without a non-photosensitive resin layer, A conductive layer for forming a conductive pattern on the aforementioned wiring circuit board, A precursor to the insulating layer of the wiring circuit board, and a photosensitive resin layer disposed on the conductor layer. A metal-clad laminate equipped with the following features.

9. The metal-clad laminate according to claim 8, wherein the photosensitive resin layer is disposed on the conductive layer via a photosensitive adhesive layer.

10. The metal-clad laminate according to claim 8 or 9, further comprising a photosensitive adhesive layer disposed on the photosensitive resin layer.

11. The metal-clad laminate according to claim 8 or 9, further comprising a second conductor layer disposed on the photosensitive resin layer for forming a second conductor pattern of the wiring circuit board.

12. The metal-clad laminate according to claim 11, wherein the second conductor layer is disposed on the photosensitive resin layer via a photosensitive adhesive layer.

13. The metal-clad laminate according to claim 11 or 12, wherein the second conductor layer is made of copper.

14. The metal-clad laminate according to any one of claims 8 to 13, wherein the conductive layer is made of copper.

15. The photosensitive resin layer is made of photosensitive polyimide, as described in any one of claims 1 to 14.

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