Circuit board and electronic device including same

Abstract

Disclosed are a circuit board and an electronic device including same. A circuit board according to one aspect of the present invention may include: a base substrate having a defined protective layer formation area; a wiring pattern formed on the base substrate, the wiring pattern being formed in the protective layer formation area; a terminal formed on the base substrate, the terminal being formed outside the protective layer formation area; an extension pattern extending to connect the wiring pattern and the terminal and formed on the base substrate; a protective layer formed of a protective material and fixed on the protective layer formation area; and a dam pattern extending from the extension pattern and formed on the base substrate to prevent the protective material from flowing beyond the protective layer formation area toward the terminal when the protective layer is formed.

Description

Circuit board and electronic device including same

[0001] The present invention relates to a circuit board and an electronic device including the same.

[0002] A conventional circuit board includes a wiring area covered with a protective layer and a connection terminal area not covered with solder resist, and the connection terminals of the connection terminal area are connected to the wiring pattern of the wiring area.

[0003] The connection terminal area is the area where electronic components are mounted or connected to external electronic devices, so the connection terminals corresponding to the conductor wiring are exposed.

[0004] Meanwhile, solder resist is mainly used as the protective layer, and the solder resist is formed in the form of a liquid paste of epoxy resin series on the wiring area by printing or coating, and goes through a heat treatment hardening step.

[0005] Because solder resist is applied in liquid form, it tends to smear at the interface. To prevent this smearing, it's important to maintain sufficient spacing between terminals and wiring.

[0006] However, with the recent increase in integration of electronic devices, the need for improved wiring density on circuit boards has arisen, such as reducing the pitch between wires and the gap between terminals and wires. To address this technological trend, when the gap between terminals and wires on conventional circuit boards is narrowed, the solder resist's spreading characteristics cause solder resist to form all the way to the terminals, lowering the reliability of connections with components or external electronic devices.

[0007] In particular, the problem of solder resist spreading to the terminal along the extension wiring where the terminal and wiring are connected is becoming a major factor in reducing connection reliability.

[0008] The present invention is intended to solve the above problems, and an object of the present invention is to provide a circuit board configured to prevent a protective material such as solder resist from spreading to the terminals.

[0009] The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0010] According to one aspect of the present invention, a circuit board is provided, comprising: a base substrate having a defined protective layer formation area; a wiring pattern formed on the base substrate and formed in the protective layer formation area; a terminal formed on the base substrate outside the protective layer formation area; an extension pattern formed on the base substrate and extending to connect the wiring pattern and the terminal; a protective layer formed of a protective material fixed on the protective layer formation area; and a dam pattern formed on the base substrate and extending from the extension pattern to prevent the protective material from flowing toward the terminal beyond the protective layer formation area when the protective layer is formed.

[0011] At this time, the dam pattern can be formed to extend from one side and the other side of the extension pattern, respectively.

[0012] Meanwhile, the above dam pattern can be extended in a straight line shape.

[0013] Meanwhile, the dam pattern may include a straight extension portion connected to the extension pattern and extending in a straight shape; and a bent portion bent at an end of the straight extension portion to surround the terminal.

[0014] Meanwhile, the above dam pattern may be extended in a concave curved shape toward the terminal.

[0015] Meanwhile, the dam pattern may have a shape corresponding to the shape of the boundary line of the protective layer formation area facing the terminal.

[0016] Meanwhile, at least one groove may be formed in some area of ​​the side of the above extension pattern.

[0017] At this time, the groove may be formed in an area between the boundary line of the protective layer formation area and the dam pattern on the side of the extension pattern.

[0018] According to another aspect of the present invention, an electronic device including the circuit board is provided.

[0019] According to the above configuration, a circuit board according to one aspect of the present invention includes a dam pattern formed by extending from an extension pattern, thereby effectively preventing a protective material from flowing toward a terminal beyond a protective layer formation area when forming a protective layer.

[0020] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the composition of the invention described in the claims.

[0021] FIG. 1 is a drawing showing a portion of a circuit board according to one embodiment of the present invention.

[0022] Figure 2 is a drawing showing the process of forming a protective layer in some areas shown in Figure 1.

[0023] Figure 3 is a drawing showing a variation of the dam pattern illustrated in Figure 2.

[0024] Figure 4 is a drawing showing another variation of the dam pattern illustrated in Figure 2.

[0025] FIG. 5 is a drawing showing a variation of the extension pattern shown in FIGS. 1 and 2.

[0026] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice the present invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein. To clearly explain the present invention, parts irrelevant to the description are omitted in the drawings, and the same reference numerals designate identical or similar components throughout the specification.

[0027] The words and terms used in this specification and claims should not be construed as limited to their ordinary or dictionary meanings, but should be interpreted in a way that is consistent with the technical idea of ​​the present invention, in accordance with the principles by which the inventor can define terms and concepts in order to best explain his or her invention.

[0028] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings correspond to a preferred embodiment of the present invention, and do not represent all of the technical ideas of the present invention, so there may be various equivalents and modified examples that can replace the configuration at the time of filing of the present invention.

[0029] In this specification, terms such as “include” or “have” are intended to describe the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but should be understood not to exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0030] When a component is said to be "in front of," "behind," "above," or "below" another component, this includes not only being placed "in front of," "behind," "above," or "below" the other component in direct contact with it, but also if there is another component intervening therebetween. Furthermore, when a component is said to be "connected" to another component, this includes not only being directly connected to one another, but also being indirectly connected to one another, unless there are special circumstances.

[0031] Hereinafter, a circuit board according to one embodiment of the present invention will be described with reference to the drawings.

[0032] FIG. 1 is a drawing showing a portion of a circuit board according to one embodiment of the present invention.

[0033] Referring to FIG. 1, a circuit board (1) according to the present embodiment includes a base board (10), a wiring pattern (20), a terminal (30), an extension pattern (40), a protective layer (50), and a dam pattern (60).

[0034] A base substrate (10) is included as a substrate of a circuit board (1). The base substrate (10) is formed of a flexible material so that the circuit board (1) can be folded. The base substrate (10) may be formed of an insulating material.

[0035] Specifically, in this embodiment, the base substrate (10) may be a polyimide (PI) film. In addition, the base substrate (10) may be made of a material selected from a group of polymers including polyester (PE), polyethylene terephthalate (PET), polyethylene napthalene (PEN), polycarbonate (PC), etc.

[0036] Meanwhile, the base substrate (10) may be made of a metal foil such as aluminum oxide foil.

[0037] In this embodiment, a protective layer formation region (SR) is defined on the base substrate (10). The protective layer formation region (SR) is a region where a protective layer (50) is formed to prevent damage to the wiring pattern (20) formed on the base substrate (10). A protective material is fixed to the protective layer formation region (SR) to form a protective layer (50).

[0038] The wiring pattern (20) is formed on the base substrate (10).

[0039] For example, a wiring pattern (20) is formed on the base substrate (10) to electrically connect two points on the base substrate (10) or to electrically connect one point on the base substrate (10) to the outside.

[0040] For example, a terminal (30) described later may be formed at a point connected to a wiring pattern (20). At this time, the wiring pattern (20) and the terminal (30) are electrically connected by an extension pattern (40) described later.

[0041] The wiring pattern (20) is formed in the protective layer formation region (SR) and is protected by the protective layer (50).

[0042] It is preferable that the wiring pattern (20) be made of a highly conductive material.

[0043] For example, the wiring pattern (20) may be made of a conductive metal such as gold, aluminum, copper, etc.

[0044] At least one wiring pattern (20) can be formed on the base substrate (10). There is no limitation on the number of wiring patterns (20).

[0045] The wiring pattern (20) is not limited to being formed on one side of the base substrate (10), and may also be formed on the other side of the base substrate (10) depending on the purpose of use, shape, etc. of the circuit board (1).

[0046] A terminal (30) is formed on the base substrate (10). The terminal (30) is a part where electronic components are mounted or comes into contact with an external electronic device.

[0047] It is preferable that the terminal (30) be made of a highly conductive material. For example, the terminal (30) may be made of a conductive metal such as gold, aluminum, copper, etc.

[0048] At least one terminal (30) can be formed on the base substrate (10). For example, a wiring pattern (20) and a terminal (30) are in a corresponding relationship, and the corresponding wiring pattern (20) and terminal (30) are connected by an extension pattern (40).

[0049] When there are multiple terminals (30), the multiple terminals (30) can be spaced apart and arranged along the boundary line (SRL) of the protective layer formation region (SR).

[0050] For reference, not all wiring patterns (20) and terminals (30) illustrated in FIG. 1 are given drawing symbols, and not all terminals (30) corresponding to all wiring patterns (20) are illustrated, and the idea of ​​the present invention is not limited to the contents illustrated in FIG. 1.

[0051] The extension pattern (40) is extended to connect the wiring pattern (20) and the terminal (30). The extension pattern (40) is formed on the base substrate (10).

[0052] It is preferable that the extension pattern (40) be made of a highly conductive material. For example, the extension pattern (40) may be made of a conductive metal such as gold, aluminum, copper, etc.

[0053] For example, a wiring pattern (20), an extension pattern (40), and a terminal (30) corresponding to each other can be sequentially formed on a base substrate (10).

[0054] For example, the wiring pattern (20), the extension pattern (40), and the terminal (30) may be sequentially formed on the base substrate (10). Alternatively, the terminal (30), the extension pattern (40), and the wiring pattern (20) may be sequentially and continuously formed on the base substrate (10).

[0055] As another example, corresponding wiring patterns (20), extension patterns (40), and terminals (30) can be formed simultaneously on the base substrate (10).

[0056] When the wiring pattern (20), extension pattern (40), and terminal (30) are formed sequentially or simultaneously as above, the manufacturing process of the circuit board (1) can be simplified and the manufacturing time can be shortened.

[0057] In this embodiment, the wiring pattern (20) and the extension pattern (40) may intersect at an obtuse angle as illustrated in FIG. 1. In other words, the wiring pattern (20) and the extension pattern (40) may intersect at an angle as illustrated in FIG. 1.

[0058] In this case, the stress generated at the intersection of the wiring pattern (20) and the extension pattern (40) due to external force is relatively smaller than when the wiring pattern and the extension pattern are at a right angle, so that the structural stability of the circuit board (1) can be improved.

[0059] On the other hand, the terminal (30) and the extension pattern (40) may intersect at an angle. In this case, the stress generated at the intersection of the terminal (30) and the extension pattern (40) due to an external force is relatively smaller than when the terminal and the extension pattern are at a right angle, thereby improving the structural stability of the circuit board (1).

[0060] The protective layer (50) is formed to protect the wiring pattern (20) from external impact, corrosion-causing substances, etc. Specifically, the protective layer (50) can be formed by a protective material fixed on a protective layer formation region (SR) defined on the base substrate (10).

[0061] In one embodiment of the present invention, the protective material forming the protective layer (50) may be solder resist ink (SR Ink). That is, the protective layer (50) may be formed by applying solder resist ink over the protective layer formation region (SR).

[0062] Figure 2 is a drawing showing the process of forming a protective layer in some areas shown in Figure 1. Here, arrows indicate the direction of movement of a protective material provided in a protective layer formation area (SR) but moving beyond the protective layer formation area (SR).

[0063] Referring to FIGS. 1 and 2, a dam pattern (60) is formed on the base substrate (10) by extending from the extension pattern (40) to prevent the protective material from flowing beyond the protective layer formation region (SR) toward the terminal (30) when forming the protective layer (50).

[0064] The protective material forming the protective layer (50) plays a role in protecting the wiring pattern (20) from external impact, corrosion-causing substances, etc., but if the protective material spreads to the terminal formation area, it contaminates the terminal (30) formed in the terminal formation area, thereby reducing the reliability of the bonding between the terminal (30) and other electronic components.

[0065] In order to prevent such a problem, when forming a protective layer (50), the applied protective material must be fixed only within the protective layer formation area (SR) of the base substrate (10), and must not flow into other areas of the base substrate (10), especially the area where the terminal (30) is formed.

[0066] The dam pattern (60) prevents the phenomenon of the protective material applied when forming the protective layer (50) from bleeding beyond the protective layer formation area (SR) to the terminal (30) by physically blocking the flow of the protective material.

[0067] That is, the dam pattern (60) acts as a barrier to the protective material.

[0068] In this embodiment, the dam pattern (60) may be formed in an area between the boundary line (SRL) of the protective layer formation area (SR) and the terminal (30). At this time, the dam pattern (60) may be positioned so as to be spaced apart from the terminal (30) and also spaced apart from the boundary line (SRL) of the protective layer formation area (SR).

[0069] For example, the gap (g) between the corresponding dam pattern (60) and the terminal (30) may be 5 μm or more. If the gap (g) between the corresponding dam pattern (60) and the terminal (30) is less than 5 μm, there is a possibility that a short circuit may occur between the dam pattern (60) and the terminal (30) during the pattern forming process.

[0070] Therefore, it is preferable that the gap (g) between the corresponding dam pattern (60) and terminal (30) be 5 μm or more.

[0071] The dam pattern (60) can be extended from the extension pattern (40) to cover the side facing the protective layer formation region (SR) of the terminal (30). In this case, the protective material flowing out of the protective layer formation region (SR) toward the terminal (30) can be effectively blocked.

[0072] In this embodiment, the dam pattern (60) is formed to extend from one side and the other side of the extension pattern (40). At this time, the dam pattern (60) extends in a form that branches laterally from the extension pattern (40).

[0073] For example, the dam pattern (60) may be formed to extend on one side and the other side in the width direction of the extension pattern (40). For reference, since the extension pattern (40) extends from the end of the wiring pattern (20) toward the terminal (30), the extension direction of the extension pattern (40) is a direction from the end of the wiring pattern (20) toward the terminal (30) or a direction from the terminal (30) toward the end of the wiring pattern (20).

[0074] As an example, the dam pattern (60) may be extended in a straight line shape as shown in FIGS. 1 and 2. In this case, the protective material flowing out of the protective layer formation region (SR) toward the terminal (30) may be blocked by the dam pattern (60) and distributed to the surrounding area of ​​the terminal (30) along the dam pattern (60).

[0075] The dam pattern (60) extended in a straight line shape like this is simple in shape and thus easy to manufacture.

[0076] As another example, the dam pattern (60') may have a shape that extends in a straight shape as in FIG. 3, but is bent so that the end wraps around the terminal (30). In other words, the dam pattern (60') may be configured to include a straight portion (61) that is connected to the extension pattern (40) and extends in a straight shape, and a bent portion (62) that is bent so as to wrap around the terminal (30) at the end of the straight portion (61). For reference, FIG. 3 is a drawing showing a modified example of the dam pattern illustrated in FIG. 2.

[0077] In this case, the protective material moving laterally along the straight-line portion (61) of the dam pattern (60') can be effectively distributed from the bent portion (62) of the dam pattern (60') to the surrounding area of ​​the terminal (30). For reference, the direction of the arrow in Fig. 3 indicates the direction of movement of the protective material.

[0078] As another example, the dam pattern (60") may extend in a concave curved shape toward the terminal (30) as shown in FIG. 4.

[0079] In this case, the protective material flowing out of the protective layer formation region (SR) toward the terminal (30) can be easily distributed to the surrounding area of ​​the terminal (30) along the curved dam pattern (60"). For reference, FIG. 4 is a drawing showing another modified example of the dam pattern shown in FIG. 2, and the direction of the arrow in FIG. 4 indicates the direction of movement of the protective material.

[0080] In this case, the protective material flowing toward the terminal (30) along the extension pattern (40) does not accumulate at the intersection of the extension pattern (40) and the dam pattern (60"), but can easily move to the surrounding area of ​​the terminal (30) along the curved surface of the dam pattern (60").

[0081] Meanwhile, referring to FIGS. 1 and 2, the dam pattern (60) may have a shape corresponding to the shape of the boundary line (SRL) of the protective layer formation region (SR) facing the terminal (30).

[0082] For example, referring to FIG. 2, if the protective layer forming region (SR) facing the terminal (30) has a straight shape, the dam pattern (60) may have a straight shape correspondingly.

[0083] As another example, if the protective layer formation area facing the terminal has a curved shape, which is not shown, the dam pattern may have a curved shape accordingly.

[0084] In this way, when the dam pattern (60) has a shape corresponding to the shape of the boundary line (SRL) of the protective layer formation region (SR) facing the terminal (30), the distance between the boundary line (SRL) of the protective layer formation region (SR) and the dam pattern (60) can be maintained the same along the extension direction of the dam pattern (60).

[0085] In this case, the dam pattern (60) can block overflow of the protective material with the same probability throughout the entire section in the extension direction.

[0086] Meanwhile, referring to FIGS. 1 and 2, the boundary line (SRL) of the protective layer formation region (SR) has a straight line shape, and a plurality of terminals (30) can be arranged spaced apart along the boundary line (SRL) facing each other.

[0087] At this time, the dam pattern (60) protrudes in the extension direction of the boundary line (SRL) based on the side end of the corresponding terminal (30), that is, the side end in the extension direction of the boundary line (SRL) of the protective layer formation region (SR).

[0088] Hereinafter, the length (d1) in the extension direction of the boundary line (SRL) from the side end of the terminal (30) to the protruding end of the dam pattern (60) is referred to as the protruding length (d1) of the dam pattern (60).

[0089] For example, the protrusion length (d1) of the dam pattern (60) exceeds 0. And the protrusion length (d1) of the dam pattern (60) is less than 0.5 times the distance (d2) between the corresponding terminal (30) and another terminal (30) adjacent in the extension direction of the boundary line (SRL).

[0090] If the protrusion length (d1) of the dam pattern (60) is more than 0.5 times the spacing (d2) between a pair of neighboring terminals (30), the dam pattern (60) may be connected to another neighboring dam pattern (60), causing a short circuit.

[0091] Therefore, it is preferable that the protrusion length (d1) of the dam pattern (60) exceeds 0 and is less than 0.5 times the distance (d2) between the corresponding terminal (30) and another terminal (30) adjacent in the extension direction of the boundary line (SRL).

[0092] The relationship between the protrusion length (d1) of the dam pattern (60) and the spacing (d2) between a pair of adjacent terminals (30) described above through FIGS. 1 and 2 can be equally applied to the dam patterns (60', 60") illustrated in FIGS. 3 and 4.

[0093] Meanwhile, Fig. 5 is a drawing showing a modified example of the extension pattern illustrated in Figs. 1 and 2. Referring to Fig. 5, at least one groove (41) may be formed in a portion of a side surface of the extension pattern (40'). The groove (41) may be formed on at least one of one side surface and the other side surface in the width direction of the extension pattern (40').

[0094] The protective material flowing out from the protective layer formation region (SR) can be distributed to the surrounding area of ​​the terminal (30) through the extension pattern (40') in which the groove (41) is formed and the dam pattern (60). For reference, the direction of the arrow in Fig. 5 indicates the direction of movement of the protective material.

[0095] The home (41) slows down the movement of the protective material flowing toward the terminal (30) along the extension pattern (40') beyond the protective layer formation area (SR) and disturbs the movement of the protective material.

[0096] In particular, when the amount of protective material flowing out from the protective layer formation region (SR) is not large, the protective material can be effectively dispersed around the extension pattern (40') by slowing down and disrupting the movement speed by the groove (41) of the extension pattern (40') before reaching the dam pattern (60).

[0097] It is preferable that the groove (41) be formed in the area between the boundary line (SRL) of the protective layer formation area (SR) and the dam pattern (60) on the side of the extension pattern (40'). This is because, if the groove (41) is formed in the protective layer formation area (SR), it cannot perform the above function.

[0098] The circuit board (1) according to the present embodiment as described above prevents contamination of the terminal (30) and improves the reliability of the connection between the terminal (30) and the electronic component by preventing the protective material from flowing toward the terminal (30) beyond the protective layer formation region (SR) through the dam pattern extended from the extension pattern (40) connecting the wiring pattern (20) and the terminal (30) through the protective material.

[0099] A circuit board (1) like this can form part of an electronic device such as a camera module, inductor, antenna, etc.

[0100] Although the embodiments of the present invention have been described, the spirit of the present invention is not limited to the embodiments presented in this specification, and those skilled in the art who understand the spirit of the present invention will be able to easily propose other embodiments by adding, changing, deleting, or adding components within the scope of the same spirit, but this will also be considered to fall within the spirit of the present invention.

Claims

1. Base substrate with defined protective layer formation area; A wiring pattern formed on the base substrate and formed in the protective layer forming region; A terminal formed on the base substrate outside the protective layer formation area; An extension pattern formed on the base substrate and extending to connect the wiring pattern and the terminal; A protective layer formed with a protective material fixed on the protective layer formation area; and A circuit board including a dam pattern formed on the base substrate and extending from the extension pattern to prevent the protective material from flowing toward the terminal beyond the protective layer formation area when forming the protective layer.

2. In paragraph 1, The above dam pattern is, A circuit board formed with extensions on one side and the other side of the above extension pattern.

3. In paragraph 1, The above dam pattern is a circuit board extending in a straight line shape.

4. In paragraph 1, The above dam pattern is, A straight extension connected to the above extension pattern and having a straight shape; and A circuit board comprising a bend portion that is bent to wrap around the terminal at the end of the straight extension portion.

5. In paragraph 1, The circuit board, wherein the above dam pattern extends in a concave curved shape toward the terminal.

6. In paragraph 1, A circuit board in which the above dam pattern has a shape corresponding to the shape of the boundary line of the protective layer formation area facing the terminal.

7. In paragraph 1, A circuit board, wherein at least one groove is formed in a portion of a side surface of the above extension pattern.

8. In paragraph 7, A circuit board, wherein the above groove is formed in an area between the boundary line of the protective layer formation area and the dam pattern among the sides of the above extension pattern.

9. An electronic device comprising a circuit board according to any one of claims 1 to 8.

Images