Circuit board, manufacturing method thereof, and electronic device including said circuit board

Abstract

The present invention provides a circuit board including contact terminals on a side surface, a manufacturing method thereof, and an electronic device including the circuit board, the circuit board including a base layer, a wiring layer formed on the base layer, and a terminal portion formed at a level corresponding to the wiring layer and formed on one surface and the side surface at one end of the base layer.

Description

[Technical field]

[0001] The present invention relates to a circuit board, a manufacturing method thereof, and an electronic device including the circuit board. More particularly, the present invention relates to a circuit board including multiple layers, a manufacturing method thereof, and an electronic device including the circuit board. [Background technology]

[0002] 2. Description of the Related Art In recent years, with the development of electronic devices and the technologies for embedding components in electronic devices, the technologies related to the manufacture of printed circuit boards (PCBs) are also continuously developing.

[0003] Generally, printed circuit boards can be classified into single-sided printed circuit boards, double-sided printed circuit boards, multi-layer printed circuit boards, etc., depending on the number of wiring circuit sides. Here, multi-layer printed circuit boards can be used in high-precision devices such as computers, mobile phones, and high-performance communication devices.

[0004] A multi-layer printed circuit board may be formed by stacking a number of flexible printed circuit boards (FPCBs) on which circuit patterns are printed, and the circuits printed on each layer may be electrically connected via through holes. Summary of the Invention [Problem to be solved by the invention]

[0005] In the case of multi-layer printed circuit boards, bottom bonding (flat bonding) is usually used when bonding boards. In this case, the pads formed on each board can be soldered to each other.

[0006] However, when bonding the boards in this manner, shift defects can occur in the x and y directions between the two upper and lower boards, and floating defects can occur in the z direction during soldering.

[0007] Furthermore, solder bubbles and poor joints cannot be seen with the naked eye, and may result in bending of the contact surfaces of the boards.

[0008] An object of the present invention is to provide a circuit board including contact terminals on a side surface thereof, a method for manufacturing the same, and an electronic device including the circuit board.

[0009] The object of the present invention is not limited to the above-mentioned objects, and other objects not mentioned herein will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0010] One aspect of the circuit board of the present invention for achieving the above object includes a base layer; a wiring layer formed on the base layer; and a terminal portion formed at a level corresponding to the wiring layer and formed on one surface and a side surface at one end of the base layer.

[0011] The terminal portion may be a part of the wiring layer.

[0012] The height of the terminal portion may be the same as the height of the wiring layer, or may be lower than the height of the wiring layer.

[0013] The terminal portion may be formed by forming a photoresist on both sides of the base layer and then performing an exposure process multiple times.

[0014] At least two of the multiple exposure processes may be performed under different conditions.

[0015] The terminal portion can be formed by sequentially carrying out exposure processes in an area on one side of the base material layer where the terminal portion is to be formed, an area on one side of the base material layer where the wiring layer is to be formed, and an area on the other side of the base material layer where the wiring layer and the terminal portion are to be formed.

[0016] The terminal portion may be formed by being bent at least once.

[0017] The terminal portion may be made of a conductive material.

[0018] The terminals formed on the side surface of the circuit board may have a height equal to or lower than one end of the side surface of the board in the thickness direction.

[0019] The wiring layer may be a spiral coil pattern, and the terminal portion may include a coil connected to the coil pattern.

[0020] One embodiment of an electronic device of the present invention for achieving the above-mentioned object includes a circuit board; a connection conductor joined to the circuit board using a conductive adhesive; and a device installed at a distance from the circuit board, the circuit board including a base layer; a wiring layer formed on the base layer; and a terminal portion formed at a level corresponding to the wiring layer and formed on one surface and a side surface at one end of the base layer.

[0021] The device may include a magnetic material.

[0022] The height of the solder at the time of soldering the circuit board and the connecting conductor may be less than the height of the circuit board.

[0023] One embodiment of a method for manufacturing a circuit board of the present invention for achieving the above object includes the steps of: when a circuit board including a base layer, a first wiring layer, and an insulating layer is provided, forming a through hole on the outer periphery of the insulating layer; forming a metal foil film and a plating resist on both sides of the circuit board; performing an exposure process and a development process on the circuit board; and forming a second wiring layer and a terminal portion on the upper and side portions of the insulating layer.

[0024] Specific details of other embodiments are included in the detailed description and drawings. Effect of the Invention

[0025] According to the present invention, by using side contact terminals, it is possible to prevent deterioration of the quality of the circuit board due to contact when soldering between a circuit board and an electronic component, or when soldering between two different circuit boards. [Brief description of the drawings]

[0026] [Figure 1] 1 is a cross-sectional view illustrating a schematic structure of a circuit board according to a first embodiment of the present invention. [Diagram 2] 3A to 3C are exemplary views for explaining a method of forming a terminal portion constituting a circuit board according to a first embodiment of the present invention. [Diagram 3] FIG. 5 is a cross-sectional view illustrating a schematic structure of a circuit board according to a second embodiment of the present invention. [Figure 4] 1A and 1B are diagrams showing a structure of a side terminal according to an embodiment. [Diagram 5] 5 is an exemplary view for explaining a problem that occurs when the side terminal is formed as in FIG. 4; FIG. [Figure 6] 1A to 1C are diagrams showing the structure of a side terminal according to an embodiment of the present invention; [Figure 7] 7 is an exemplary view for explaining the effect when the side terminals are formed as in FIG. 6. FIG. [Figure 8] 2 is a flow chart that illustrates a schematic diagram of a method for manufacturing a circuit board according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention, as well as methods for achieving the same, will become apparent from the following detailed embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be realized in various different forms. The present embodiments are provided merely to complete the disclosure of the present invention and to fully inform those skilled in the art of the present invention of the scope of the invention, and the present invention is defined only by the scope of the claims. The same reference symbols refer to the same elements throughout the specification.

[0028] When elements or layers are referred to as "on" or "on" another element or layer, this includes not only directly on the other element or layer, but also when there are other layers or elements in between. Conversely, when an element is referred to as "directly on" or "directly above" it means that there are no other elements or layers in between.

[0029] Spatially relative terms such as "below," "beneath," "lower," "above," "upper," and the like, are used to facilitate describing the relationship of one element or component to another element or component as depicted in the drawings. Spatially relative terms should be understood to include different orientations of the elements in use or operation in addition to the orientation depicted in the drawings. For example, if an element depicted in the drawings is flipped over, an element described as "below" or "beneath" another element may be placed "above" the other element. Thus, the exemplary term "below" can include both an orientation of below and above. Elements may be oriented in other directions, so the spatially relative terms can be interpreted according to the orientation.

[0030] Although the terms "first" and "second" are used to describe various elements, components, and / or sections, it is understood that these elements, components, and / or sections are not limited by these terms. These terms are used merely to distinguish one element, component, or section from another element, component, or section. Thus, it is understood that a first element, first component, or first section referred to below may be a second element, second component, or second section within the technical spirit of the present invention.

[0031] The terms used in the present specification are for the purpose of describing the embodiments and are not intended to limit the present invention. In the present specification, the singular form includes the plural form unless otherwise specified in the context. When used in the specification, "comprises" and / or "comprising" refers to a reference component, step, operation, and / or element, the term does not exclude the presence or addition of one or more other components, steps, operations, and / or elements.

[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used in the sense commonly understood by those having ordinary skill in the art to which the present invention belongs. Furthermore, terms defined in commonly used dictionaries are not idealized or overly interpreted unless specifically and explicitly defined.

[0033] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the description with reference to the accompanying drawings, the same or corresponding components will be given the same reference numbers regardless of the drawing numbers, and duplicate descriptions related thereto will be omitted.

[0034] The present invention relates to a circuit board including contact terminals on a side surface thereof, a manufacturing method thereof, and an electronic device including the circuit board.

[0035] FIG. 1 is a cross-sectional view that illustrates a schematic structure of a circuit board according to a first embodiment of the present invention.

[0036] According to FIG. 1, the circuit board 100 can include a base layer 110, a wiring layer 120, and a terminal portion .

[0037] The circuit board 100 is a substrate on which semiconductor elements are mounted, and can be attached to electronic components or electronic devices (e.g., displays, smartphones, digital cameras, etc.). The circuit board 100 can be a flexible circuit board, but can also be a rigid circuit board or a rigid-flexible circuit board. The circuit board 100 can also be a single-layer or multi-layer substrate coil.

[0038] A plurality of circuit boards 100 may be stacked to form a multi-layer board. In this case, the wiring layers formed on the boards arranged above and below each other may be electrically connected through vias.

[0039] The substrate layer 110 constitutes a base substrate. The substrate layer 110 may be formed of a base film having a predetermined thickness (for example, 5 μm to 100 μm).

[0040] The base layer 110 may be made of at least one material selected from various insulating polymer materials, for example, polyimide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate, epoxy, and glass fiber.

[0041] The wiring layer 120 serves to electrically connect the semiconductor device to an external electronic device. The wiring layer 120 may be formed as a plurality of electrode lines on one or both sides of the base layer 110. For example, when the circuit board 100 is a substrate-type coil, the wiring layer 120 may be formed as a coil pattern formed in a spiral shape on the base layer 110.

[0042] The wiring layer 120 may be manufactured using at least one metal selected from conductive metals such as nickel (Ni), chromium (Cr), copper (Cu), gold (Au), silver (Ag), platinum (Pt), aluminum (Al), etc. The wiring layer 120 may be formed on the base layer 110 using an etching process or a plating process such as an additive process, a semi-additive process, printing, coating, etc.

[0043] When an electronic component is attached to the circuit board 100, the terminal portion 130 is The terminal portion 130 is a pad formed for electrical connection between components. In the present embodiment, the wiring layer 120 for external connection (e.g., electrical connection with electronic components) may be defined as the terminal portion 130. The terminal portion 130 may be formed in an outer region of the base layer 110 to have the same height as the wiring layer 120.

[0044] The terminal unit 130 may be realized as a contact terminal for contact between the circuit board 100 and an electronic component. The terminal unit 130 may be formed of a conductive material, and in this case, may be realized as a conductive contact terminal. For example, if the circuit board 100 is a substrate-type coil, the terminal unit 130 may include a coil and may be formed as a connection terminal pad connected to a coil pattern.

[0045] The terminal portion 130 may be formed using the same metal as the wiring layer 120. The terminal portion 130 may be formed using, for example, copper (Cu). However, this embodiment is not limited thereto. The terminal portion 130 may also be formed using a metal different from that of the wiring layer 120. In this embodiment, the terminal portion 130 may be made of any metal as long as it can realize an electrical connection between the circuit board 100 and the electronic component.

[0046] When the terminal unit 130 is formed in the outer region of the base layer 110, it may be formed as a side terminal from a side end of the base layer 110 to one surface of the base layer 110. In this case, the terminal unit 130 may be formed in an inverted L shape.

[0047] The terminal unit 130 may be formed by forming a through hole 210 in the base layer 110 as shown in FIG. 2, and then filling the through hole 210 with a conductive material. To be more specific, the through hole 210 may be formed in the base layer 110 first, and then, when forming the wiring layer 120 on the base layer 110, the terminal unit 130 may be formed to fill the through hole 210, and then, a portion of a region 220 of the base layer 110 located on the outer periphery of the through hole 210 may be removed. Also, a conductive material may be formed on the inner wall of the through hole 210 to a certain thickness so as not to fill the entire hole, and the portion of the region 220 of the base layer 110 may be removed. Also, when removing the portion of the region 220 of the base layer 110, the inner part of the through hole 210 may be removed as well. FIG. 2 is an exemplary view for explaining a method of forming a terminal unit constituting a circuit board according to the first embodiment of the present invention.

[0048] Meanwhile, the terminal unit 130 may be formed separately from the wiring layer 120, and may be formed to cover the first wiring 230 formed adjacent to the side of the base layer 110 as shown in Fig. 3. In this case, the terminal unit 130 may be formed to have the same height as the other wiring, i.e., the second wiring 240, other than the first wiring 230 formed on the base layer 110. The terminal unit 130 may also be formed to have a height greater than that of the second wiring 240. Fig. 3 is a cross-sectional view illustrating a schematic structure of a circuit board according to a second embodiment of the present invention.

[0049] When the terminal unit 130 is formed to cover the first wiring 230, it may be formed to cover the upper part of the first wiring 230. However, the present embodiment is not limited thereto. The terminal unit 130 may be formed to cover not only the upper part of the first wiring 230 but also the side part thereof. In this case, the terminal unit 130 may be formed to cover the entire or a part of the upper part of the first wiring 230, and may be formed to cover the entire or a part of the side part of the first wiring 230.

[0050] Referring again to FIG.

[0051] When the terminal portion 130 is formed on the base layer 110, the same photoresist is formed on both sides of the base layer 110. After forming the resist, the exposure process can be carried out two or more times under different conditions. More specifically, the exposure process can be carried out as follows.

[0052] First, a primary exposure is performed on an area where the terminal portion 130 is to be formed on one surface of the base layer 110. In this case, in this embodiment, half exposure may be performed to a depth where the terminal portion 130 is not to be formed on the inner wall of the hole.

[0053] Thereafter, a second exposure is performed on the surface of the base layer 110 in an area where the wiring layer 120 is to be formed.

[0054] Thereafter, a tertiary exposure is performed on the region where the wiring layer 120 is to be formed and the region where the terminal portion 130 is to be formed on the other surface of the base material layer 110. In this case, in this embodiment, it is possible to expose only a portion (half) of the terminal portion 130.

[0055] Meanwhile, when another circuit board is placed on the circuit board 100, the terminal portion 130 can also be used for electrical connection between the circuit board 100 and the other circuit board.

[0056] Meanwhile, although not shown in FIG. 1, the circuit board 100 may further include at least one of a plating layer and a protective layer.

[0057] The plating layer is intended to prevent corrosion of the wiring layer 120 and the terminal portion 130 and to improve the bonding between the circuit board 100 and the semiconductor element, and between the circuit board 100 and an external electronic device. Such a plating layer may be formed so as to cover the upper portions of the wiring layer 120 and the terminal portion 130, and may be formed so as to cover not only the upper portions but also the side portions of the wiring layer 120 and the terminal portion 130.

[0058] The plating layer may be manufactured using at least one metal or an alloy of two or more metals selected from conductive metals such as tin (Sn), gold (Au), palladium (Pd), nickel (Ni), chromium (Cr), etc. The plating layer may be formed to cover the entire or part of the wiring layer 120 and the terminal unit 130 before forming a protective layer on the wiring layer 120 and the terminal unit 130.

[0059] The protective layer is formed on the wiring layer 120 to protect the wiring layer 120. Such a protective layer may be formed to cover the wiring layer 120 or the plating layer, and in this case, it may be formed to cover all or a part of the wiring layer 120, and similarly, it may be formed to cover all or a part of the plating layer. The protective layer may also be formed to cover all or a part of the terminal portion 130.

[0060] The protective layer may be formed of an insulating material (e.g., solder resist), and in this case, the protective layer may be formed by printing or coating a liquid solder resist. Meanwhile, the protective layer may be formed by adhering a protective film (e.g., a coverlay film) onto the base layer 110 by a lamination method.

[0061] Various embodiments of the terminal unit 130 constituting the circuit board 100 have been described above with reference to Figs. 1 to 3. The terminal unit 130 according to the present embodiment is a terminal capable of side contact and relates to a conductive contact terminal for mounting on a board surface. More specifically, the terminal relates to a side terminal that is installed between the contact areas of a circuit board and an electronic component or between the contact areas of two or more electronic components in a process of mounting an electronic component on a circuit board and allows side contact that is not on the top or bottom.

[0062] When a terminal hole (i.e., through hole 210) is formed by penetrating one side of one or more insulating layers (i.e., base layer 110) constituting circuit board 100, the side terminal may be formed on a part of the upper surface of the insulating layer and a part of the side of the terminal hole. In this case, the side terminal may be formed by folding at least once.

[0063] Next, an electronic device including the circuit board 100 will be described.

[0064] Fig. 4 is a view showing a structure of a side terminal according to an embodiment, and Fig. 5 is an example view for explaining a problem when the side terminal is formed as shown in Fig. 4. Fig. 6 is a view showing a structure of a side terminal according to an embodiment of the present invention, and Fig. 7 is an example view for explaining an effect when the side terminal is formed as shown in Fig. 6.

[0065] The electronic device 300 may include a circuit board 100, a connection conductor 310, and a magnetic body 320. For such a configuration of the electronic device 300, refer to Figs.

[0066] The connection conductor 310 is a conductor or an electronic component to be bonded to the circuit board 100. The connection conductor 310 can be bonded to the circuit board 100 using a conductive adhesive 311.

[0067] The connection conductor 310 can be realized as a conductive metal material. For example, the connection conductor 310 can be realized as a cylindrical rod of a metal material connected to the terminal portion 130. The conductive bonding material 311 can include a bonding material between conductive materials such as solder.

[0068] The magnetic body 320 may be installed at a predetermined distance from the circuit board 100. The magnetic body 320 may perform up-down or back-and-forth / left-right reciprocating motion in the direction in which the circuit board 100 is located (third direction 30) above or below the circuit board 100. The magnetic body 320 may also move so as to tilt at a predetermined angle.

[0069] 5 and 7, the connecting conductor 310 is shown as a cylindrical metal rod, but the connecting conductor 310 in this embodiment may be another circuit board, electronic component, device, etc. Also, another component may be disposed in place of the magnetic body 320. In other words, a device may be disposed.

[0070] If the connecting conductor 310 is assumed to be another circuit board, the circuit board 100 can be soldered to the connecting conductor 310 using solder. In this case, if the terminal portion 130 is made of U-shaped plating on the top, bottom and sides of the circuit board 100 in a side terminal structure as shown in Fig. 5, the solder moves upward along the terminal portion 130 and protrudes from the top of the terminal portion 130 and the connecting conductor 310, generating a coating height, which may cause a decrease in function due to contact interference with the magnetic body 320.

[0071] 6 and 7, when terminal portion 130 is formed on one surface and its side surface of circuit board 100, terminal portion 130 has a side terminal structure, and thus an inverted L-shaped plating can be performed on the upper portion and its side surface (or the lower portion and its side surface) of circuit board 100. In this case, even if the solder moves upward along terminal portion 130, its height is lowered, so that there is no effect on the height of application during soldering between circuit board 100 and connecting conductor 310, and this has the effect of preventing contact interference with magnetic body 320.

[0072] In the above case, the height h1 of the solder protruding above the base layer 110 may be lower than the height h2 of the wiring layer 120 on the base layer 110 (h1>h2). Alternatively, if a protective layer is formed on the wiring layer 120, the height of the solder may be lower than the height of the protective layer on the base layer 110. That is, in this embodiment, the height of the solder is sufficient as long as it is high enough to prevent contact between the solder and the magnetic material.

[0073] Next, a method for manufacturing the circuit board 100 will be described.

[0074] 8 is a flow chart showing a schematic method for manufacturing a circuit board according to an embodiment of the present invention, for example, a flow chart showing a schematic method for manufacturing a four-layer substrate-type coil. The following description will be made with reference to FIG.

[0075] First, a circuit board is prepared. More specifically, a double-sided circuit layer is formed on a Core PI. Hereinafter, the circuit layer is defined as an inner layer circuit. Then, double-sided insulating layer lamination is performed based on the inner layer circuit. In this embodiment, the insulating layer lamination can be performed using a roll to roll lamination method or a hot press method.

[0076] In this embodiment, once the base layer 110 is provided, the following steps can be sequentially performed on the base layer 110. However, this embodiment is not limited thereto. It is also possible to sequentially perform the steps after forming the wiring layer 120 on the base layer 110.

[0077] After forming an insulating layer on the wiring layer 120 (S410), a BVH (Blind Vector Hole) is formed at a predetermined position of the insulating layer to connect the upper wiring to be formed on the insulating layer later and the wiring layer 120. Then, through holes 210 for forming side pads are formed in the outer region of the circuit board (S420). In this embodiment, a laser drill, a CNC drill, a CNC puncher, etc. can be used as a hole processing method.

[0078] The above steps take into consideration the case where the circuit board 100 is formed as shown in Fig. 2. On the other hand, when the circuit board 100 is formed as shown in Fig. 1, that is, when the terminal portion 130 is formed on one surface and the side surface of the circuit board, the formation of the through hole 210 may be omitted.

[0079] After performing hole processing (S420), a metal foil film is formed on both sides of the circuit board including the through hole 210 using a sputter deposition method (S430). Then, a DFR, which is a plating resist, is formed on the metal foil film. More specifically, DFR lamination is performed to form an outer layer, and at this time, the filling of the hole must be ensured.

[0080] After sputtering and DFR lamination (S430), the circuit board is exposed to light (S440). At this time, the exposure process can be performed two or more times under different conditions.

[0081] For example, a primary exposure is performed on an area on one surface of the base layer 110 where the terminal unit 130 is to be formed, then a secondary exposure is performed on an area on one surface of the base layer 110 where the wiring layer 120 is to be formed, and then a tertiary exposure is performed on an area on the other surface of the base layer 110 where the wiring layer 120 is to be formed and an area on the other surface of the base layer 110 where the terminal unit 130 is to be formed. At this time, a space area is formed in a part of the side terminal area, which determines the height of the solder.

[0082] After the exposure step (S440), in the DFR development step (S450), the side terminal structure is opened in an inverted L shape on one surface of the circuit board and on its side.

[0083] Then, an upper layer circuit and terminal portion 130 are formed on the circuit board by PF (Pattern Fill) copper plating (S460).

[0084] Meanwhile, the circuit board 100 can be manufactured as a final product by sequentially going through a DFR peeling process (S470) for removing the DFR pattern and the metal foil film, an E / T process (S470), and a protective layer formation process (S480).

[0085] Here, when the circuit board 100 has a multi-layer, the side terminals can be connected to inner layer circuits.

[0086] A method for manufacturing the circuit board 100 has been described above with reference to Fig. 9. When manufacturing the circuit board 100 in this manner, side plating of the outer periphery can be achieved by exposure and development using a photosensitive resin, which can increase the effects of fine patterns, simplification of processes, cost reduction, and reduction of defects. In addition, it can meet the needs of fine patterns and packaging of the board.

[0087] Although the embodiment of the present invention has been described above with reference to the accompanying drawings, those skilled in the art will understand that the present invention can be embodied in other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the above embodiment is illustrative in all respects and is not limiting. [Industrial Applicability]

[0088] The present invention can be applied to circuit boards, coil boards, or electronic components and electronic equipment to which such boards are attached.

Claims

1. Base material layer; A wiring layer formed on the base layer; and a terminal portion formed at a level corresponding to the wiring layer and on one surface and a side surface at one end of the base layer; The terminal portion is provided from one surface of the base layer to a side surface, and is not provided on the other surface of the base layer.

2. The circuit board according to claim 1 , wherein the terminal portion is a part of the wiring layer.

3. The circuit board according to claim 1 , wherein the height of the terminal portion is the same as or lower than the height of the wiring layer.

4. The circuit board according to claim 1 , wherein the terminal portion is formed by bending at least once.

5. The circuit board according to claim 1 , wherein the terminal portion is made of a conductive material.

6. 2. The circuit board according to claim 1, wherein the terminals formed on the side surface of the circuit board are at the same height as or lower than one end of the side surface of the board in the thickness direction.

7. the wiring layer is a spiral coil pattern, The circuit board according to claim 1 , wherein the terminal portion includes a coil connected to the coil pattern.

8. Circuit board; A connection conductor joined to the circuit board using a conductive adhesive; and a device disposed apart from the circuit board; The circuit board includes: Base material layer; A wiring layer formed on the base layer; and a terminal portion formed at a level corresponding to the wiring layer and on one surface and a side surface at one end of the base layer; The terminal portion is provided from one surface of the base layer to a side surface, and is not provided on the other surface of the base layer.

9. The electronic device of claim 8 , wherein the device comprises a magnetic material.

10. 9. The electronic device of claim 8, wherein the height of the solder at the soldered joint between the circuit board and the connecting conductor is less than the height of the circuit board.

11. forming a through hole on an outer periphery of the insulating layer after providing a circuit board including a base layer, a first wiring layer, and an insulating layer; forming a metal foil film and a plating resist on both sides of the circuit board; performing an exposure process and a development process on the circuit board; and forming a second wiring layer and a terminal portion on an upper portion and a side portion of the insulating layer; The method for manufacturing a circuit board, wherein the terminal portion is formed from the upper portion to the side portion of the insulating layer, and is not formed on the lower portion of the insulating layer.

12. The terminal portion is formed by forming a photoresist on both sides of the base layer and then performing an exposure process multiple times, At least two of the multiple exposure steps are performed under different conditions; The manufacturing method according to claim 11, wherein the terminal portion is formed by sequentially carrying out exposure processes in an area on one surface of the base material layer where the terminal portion is to be formed, an area on one surface of the base material layer where the second wiring layer is to be formed, and an area on the other surface of the base material layer where the second wiring layer and the terminal portion are to be formed.

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