Flexible board product with electronic component with large welding surface
By setting solder mask bridges and copper-cutting structures on the solder pads, the problem of voids after reflow soldering of electronic components with large solder surfaces was solved, thereby improving soldering performance and increasing product yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-24
- Publication Date
- 2026-03-17
AI Technical Summary
During the FPC production process, reflow soldering voids are prone to occur in the soldering areas of large-area electronic components, affecting the electrical, thermal, and mechanical properties of the product.
Solder mask bridges are set on the pads to divide the large soldering surface into multiple small soldering branch areas, and copper-cutting structures are set at the edges of the pads to form venting channels to facilitate the discharge of gas inside the solder paste.
It effectively reduced the welding void rate from 32.1% to 1.5%, improving the product yield by 5%.
Smart Images
Figure CN224006865U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of flexible board manufacturing technology, and in particular to a flexible board product with a large welding surface for electronic components. Background Technology
[0002] In the production of Flexible Printed Circuits (FPCs), electronic components are often soldered onto the FPC. During this process, due to the characteristics of solder paste technology and materials, voids often appear in the solder areas of large solder surfaces of electronic components after reflow soldering. This can affect the electrical, thermal, and mechanical properties of the product, and may even lead to product failure. As the functional requirements of FPC products increase, the effective soldering area requirements for electronic components also become more stringent. Therefore, improving the solution to the problem of solder paste reflow voids in large solder surface area electronic components after reflow soldering has become a pressing technological challenge. Utility Model Content
[0003] This invention provides a flexible printed circuit board (FPC) product with large soldering surfaces for electronic components, which can solve the technical problem of solder paste reflow voids appearing in the soldering area of electronic components with large soldering surfaces on FPCs in traditional technology after reflow soldering.
[0004] To solve the above-mentioned technical problems, this utility model provides a flexible printed circuit board product with a large soldering surface for electronic components, comprising:
[0005] A flexible board, wherein the flexible board has pads, and the pads have soldering areas, the area of which is greater than 0.64 mm². 2 ;as well as
[0006] Electronic components are soldered to the soldering area of the solder pads.
[0007] The solder pad is provided with at least one solder resist bridge, which is used to divide the soldering area into multiple soldering branch areas, and the area of each soldering branch area is less than 0.64 mm. 2 .
[0008] Optionally, the height of the weld bridge is 0.1-0.14 mm.
[0009] Optionally, the solder mask bridge is a layer of solder mask ink printed on the solder pad.
[0010] Optionally, the welding branch area includes a main branch area located at the pad, the shape of which corresponds to the shape of the pad.
[0011] Optionally, the welding branch area includes the main branch area and a protruding area protruding from the main branch area, the protruding area at least partially protruding beyond the solder pad.
[0012] Optionally, the edge of the pad is provided with a copper-cutting structure, which extends to the inner edge of the soldering branch area.
[0013] Optionally, the copper mining structure is located at least on the long side of the welding branch area, and at the middle of the long side of the welding branch area.
[0014] Optionally, the copper mining structure is a rectangular structure with a length of 0.18-0.22 mm and a width of 0.08-0.09 mm.
[0015] Optionally, the solder mask bridge includes a protruding area that at least partially extends beyond the solder pad, the protruding area being located at the copper cut structure.
[0016] Optionally, each of the welding branch areas includes at least one of the protruding areas, and each of the protruding areas is located at one of the copper-cutting structures.
[0017] The beneficial effects of the technical solution provided by this utility model include:
[0018] On flexible circuit boards, when the soldering area of the pads for soldering electronic components is large, some gas will form bubbles after reflow soldering and remain inside the solder paste on the pads, resulting in an excessively high void rate and affecting the product's performance. By setting solder mask bridges on the pads, the soldering area of the large soldering surface can be divided into smaller soldering branches, increasing the venting channels within the solder paste during reflow soldering. This facilitates the escape of gas from the solder paste on the pads, effectively reducing the void rate of large solder pads. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a simplified planar structural diagram of the flexible printed circuit board product with large welding surface for electronic components as described in this embodiment of the present invention;
[0021] Figure 2 This is a simplified planar structural diagram of the flexible board product with large welding surface for electronic components as described in this embodiment of the utility model.
[0022] Figure 3 This is a simplified schematic diagram of a portion of the pads of the flexible board in the flexible board product with large soldering surface for electronic components, as described in this embodiment of the invention. Figure 1 ;
[0023] Figure 4 for Figure 3 A simplified schematic diagram of the cross-sectional structure of the pad portion of the flexible board;
[0024] Figure 5 This is a simplified schematic diagram of a portion of the pads of the flexible board in the flexible board product with large soldering surface for electronic components, as described in this embodiment of the invention. Figure 2 ;
[0025] Figure 6 for Figure 5 A simplified schematic diagram of the cross-sectional structure of the pad portion of the flexible board;
[0026] Figure 7 This is a simplified schematic diagram of a portion of the pads of the flexible board in the flexible board product with large soldering surface for electronic components, as described in this embodiment of the invention. Figure 3 ;
[0027] Figure 8 This is a simplified schematic diagram of a portion of the pads of the flexible board in the flexible board product with large soldering surface for electronic components, as described in this embodiment of the invention. Figure 4 .
[0028] In the diagram: 10. Flexible board product with large soldering surface for electronic components; 100. Flexible board; 110. Solder pad; 112. Solder resist ink structure; 120. Solder resist bridge; 130. Copper cutout structure; 200. Electronic component; 300. Soldering area; 310. Soldering branch area; 312. Main branch area; 314. Protruding area. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0030] like Figure 1 As shown, this utility model proposes a flexible board product 10 with a large soldering surface for electronic components, including a flexible board 100 and electronic components 200 soldered onto the flexible board 100. Further, as... Figure 2As shown, the flexible board 100 is provided with pads 110, and the area of the soldering region 300 of the pads 110 is greater than 0.64 mm². 2 Furthermore, the electronic component 200 is soldered to the soldering area 300 of the pad 110. When the area of the soldering area 300 of the pad 110 exceeds 0.64 mm²... 2 In this case, the soldering area 300 of the pad 110 can be regarded as the soldering area 300 of the large soldering surface, and the electronic components 200 soldered on the pad 110 are the components of the large soldering surface.
[0031] Among them, such as Figures 2 to 3 As shown, the flexible board has at least one solder mask bridge 120 on the solder pad 110. The solder mask bridge 120 is used to divide the soldering area 300 into multiple soldering branch areas 310, and the area of each soldering branch area 310 is less than 0.64 mm². 2 When the soldering area 300 of the pad 110 for soldering electronic components 200 on the flexible circuit board 100 is large, some gas will form bubbles after reflow soldering and remain inside the solder paste on the pad 110, resulting in an excessively high solder void rate and affecting the product's performance. By setting solder mask bridges 120 on the pad 110, the soldering area 300 of the large soldering surface of the pad 110 can be divided into soldering branch areas 310 of the smaller soldering surface. This increases the venting channels in the solder paste during reflow soldering, facilitating the discharge of gas from the solder paste on the pad 110, thereby effectively reducing the solder void rate of the large pad 110.
[0032] Specifically, such as Figures 3 to 4 As shown, the solder mask bridge 120 is a solder mask ink layer printed on the solder pad 110. That is, the solder mask bridge 120 can be printed onto the solder pad 110 of the flexible circuit board using solder mask ink. The solder mask bridge 120 divides the soldering area 300 of the large soldering surface of the solder pad 110 into multiple small soldering branch areas 310, which facilitates the venting of gas inside the solder paste on the solder pad 110 during reflow soldering. In addition, a solder mask ink structure 112 is also provided on the periphery of the solder pad 110 to isolate the soldering area 300.
[0033] For example, when the area of the soldering region 300 of the solder pad 110 on the large soldering surface exceeds 0.64 mm. 2 (For example, if the size of pad 110 is 0.8mm*0.8mm), pad bridges 120 can be set on pad 110 to divide the soldering area 300 of the large soldering surface of pad 110 into multiple soldering branch areas 310 of smaller soldering surfaces. Correspondingly, the area of each soldering branch area 310 of a small soldering surface can be less than 0.64mm². 2 (For example, the size of the welding branch area 310 of the small welding surface can be less than 0.8mm*0.8mm).
[0034] It should also be noted that the area of the welding zone 300 is not limited to 0.64 mm. 2 It can also be found at 0.64mm. 2 For example, the area of the welding region 300 could be 0.6 mm². 2 Or 0.68mm 2 This allows the area of the welding zone 300 to be between 0.6-0.68 mm. 2 Specifically, when the area of the soldering region 300 of the solder pad 110 on the large soldering surface exceeds 0.6 mm. 2 At the same time, the solder bridge 120 divides the large soldering area 300 of the solder pad 110 into multiple small soldering branch areas 310 with an area of less than 0.6 mm. 2 When the area of the soldering region 300 of the solder pad 110 on the large soldering surface exceeds 0.68mm... 2 At the same time, the solder bridge 120 divides the large soldering area 300 of the solder pad 110 into multiple small soldering branch areas 310 with an area of less than 0.68 mm². 2 .
[0035] Moreover, such as Figures 2 to 4 As shown, the height of the solder mask bridge 120 can be 0.1-0.14 mm. By setting the solder mask bridge 120 to a preset height, the soldering area 300 of the large soldering surface of the solder pad 110 is divided, forming multiple small soldering branch areas 310 on the solder pad 110, increasing the venting channels in the solder paste during reflow soldering. For example, the height of the solder mask bridge 120 can be 0.1 mm, 0.12 mm, or 0.14 mm, or any value between 0.1 and 0.14 mm. Furthermore, the width of the solder mask bridge 120 can be set according to requirements. Figure 4 In the diagram, Sn represents a solder branch region 310 with solder, and multiple solder branch regions 310 form the soldering area of the pad 110; SM between the solder branch regions 310 represents a solder mask bridge 120 formed by the solder mask ink layer, and SM outside the solder branch region 310 represents a solder mask ink structure 112 formed by solder mask ink printing; Cu and PI form a flexible board. (Below) Figure 6 Similarly.
[0036] Furthermore, each soldering branch area 310 may include a main branch area 312 disposed within the solder pad 110, the shape of the main branch area 312 corresponding to the shape of the solder pad 110. Thus, the soldering area 300 of the large soldering surface of the solder pad 110 can be divided into multiple annular soldering branch areas 310 of smaller soldering surfaces by one or more solder mask bridges 120, forming multiple venting channels on the solder pad 110. Moreover, when the solder pad 110 is rectangular or square, the annular solder mask bridge 120 can also be rectangular or square; when the solder pad 110 is circular, the main branch area 312 of the soldering branch area 310 can also be circular; when the solder pad 110 is irregularly shaped, the main branch area 312 of the soldering branch area 310 can be either an irregular shape or a regular shape.
[0037] Moreover, such as Figures 7 to 8 As shown, the soldering branch area 310 may include a main branch area 312 and a protruding area 314 protruding from the main branch area 312, the protruding area 314 at least partially protruding beyond the solder pad 110. By providing the protruding area 314 protruding beyond the solder pad 110 in the soldering branch area 310, gas on the solder pad 110 can be easily guided and discharged to the outside of the solder pad 110 through the solder mask bridge 120. Moreover, one or more protruding areas 314 may be provided on the soldering branch area 310, allowing gas on the solder pad 110 to be guided and discharged from one or more locations.
[0038] In addition, such as Figures 5 to 6 As shown, a copper-cutting structure 130 communicating with the outside can be provided at the edge of the pad 110, extending to the inner edge of the soldering branch area 310. The copper-cutting structure 130 refers to removing a portion of the copper layer of the circuit board on the flexible board through etching or machining, thereby forming a groove on the flexible board after the removal of part of the copper layer. By providing the copper-cutting structure 130 at the edges of the pad 110 and the soldering branch area 310, a height difference can be formed at the edges of the pad 110 and the soldering branch area 310, allowing gas on the pad 110 to be discharged through the height difference near the pad 110 during reflow soldering, which can further reduce the bubble void rate.
[0039] Furthermore, the copper-cutting structure 130 can be located at least along the long side of the welding branch area 310 (the welding branch area 310 can be formed by multiple sides, where the relatively longer side can be called the long side and the relatively shorter side can be called the short side), and is located in the middle of the long side of the welding branch area 310. The copper-cutting structure 130 can be located either along the long side or the short side of the welding branch area 310, creating a height difference along the long side and / or the short side of the welding branch area 310 to facilitate venting. Moreover, the copper-cutting structure 130 can be located in the middle of the long side or the middle of the short side of the welding branch area 310.
[0040] Furthermore, the copper-cutting structure 130 can be a rectangular structure with a length of 0.18-0.22 mm and a width of 0.08-0.09 mm. For example, the length of the copper-cutting structure 130 can be 0.18 mm, 0.2 mm, or 0.22 mm, etc.; correspondingly, the width of the copper-cutting structure 130 can be 0.08 mm, 0.085 mm, or 0.09 mm, etc. Moreover, the side of the copper-cutting structure 130 corresponding to (e.g., parallel to) the long side of the welding branch area 310 can be set as the long side of the copper-cutting structure 130, and the side of the copper-cutting structure 130 corresponding to (e.g., parallel to) the short side of the welding branch area 310 can be set as the short side of the copper-cutting structure 130; and the value of the long side of the copper-cutting structure 130 is its length, and the value of its short side is its width. In addition, the long side and short side of the copper-cutting structure 130, as well as the corresponding values (i.e., length) of the long side and the corresponding values (i.e., width) of the short side, can also be set according to other rules.
[0041] Moreover, such as Figures 7 to 8 As shown, when the soldering branch area 310 includes a protruding region 314 that at least partially protrudes beyond the solder pad 110, the protruding region 314 may be located at the copper-draining structure 130. By cooperating with the copper-draining structure 130, the protruding region 314 of the soldering branch area 310 can better expel gas from the solder on the solder pad 110.
[0042] Furthermore, each welding branch area 310 may include at least one protruding area 314, and each protruding area 314 may be correspondingly provided at a copper-cutting structure 130. That is, a copper-cutting structure 130 may be provided at the protruding area 314 of each solder mask bridge 120. When the welding branch area 310 has one protruding area 314, a corresponding copper-cutting structure 130 may be provided; when the welding branch area 310 has multiple protruding areas 314, multiple corresponding copper-cutting structures 130 may be provided.
[0043] This utility model provides a flexible circuit board product 10 with large soldering surfaces for electronic components. Without affecting the soldering performance of the components or increasing the process flow, it improves the problem of solder voids by changing the size of the solder pads 110 and partially removing copper, thereby increasing the airflow channels for the solder during reflow soldering. Using this design, the abnormal problem of high solder void rate on large soldering surfaces is effectively improved, reducing the solder void rate from 32.1% to 1.5%, and increasing the product yield by 5%.
[0044] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0045] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the present invention.
Claims
1. A flexible printed circuit board product with a large soldering surface for electronic components, characterized in that, The application relates to a printed circuit board (1) comprising: a flexible board having a land thereon, the land having a solder area with an area greater than 0.64 mm 2 ; and an electronic component (2) corresponding to the soldering area of the soldering pad (3); At least one soldering bridge is arranged on the soldering pad, the soldering bridge is used to divide the soldering area into multiple soldering branch areas, and the area of each soldering branch area is less than 0.64 mm 2 .
2. The flexible board product with large-surface electronic components according to claim 1, characterized in that, the height of the soldering bridge is 0.1-0.14mm.
3. The flexible board product with large-surface electronic components according to claim 1, characterized in that, The soldering bridge is a soldering resist ink layer printed on the soldering pad.
4. The flexible board product with large-surface electronic components according to claim 1, characterized in that, The soldering branch area comprises a main branch area at the soldering pad, and the shape of the main branch area corresponds to the shape of the soldering pad.
5. The flexible board product with large-surface electronic components according to claim 4, characterized in that The soldering branch area comprises the main branch area and a protruding area protruding at least partially outside the soldering pad.
6. The flexible board product with large-surface electronic components according to any one of claims 1 to 5, characterized in that The edge of the soldering pad is provided with a copper digging structure, and the copper digging structure extends to the inside of the edge of the soldering branch area.
7. The flexible board product with large-surface electronic components according to claim 6, characterized in that The copper digging structure is arranged at least at the long side of the soldering branch area and is located at the middle of the long side of the soldering branch area.
8. The flexible board product with large-surface electronic components according to claim 6, characterized in that The copper digging structure is arranged in a rectangular structure, the length of the copper digging structure is 0.18-0.22mm, and the width of the copper digging structure is 0.08-0.09mm.
9. The flexible board product with large-surface electronic components according to claim 6, characterized in that, The soldering bridge comprises a protruding area protruding at least partially outside the soldering pad, and the protruding area is located at the copper digging structure.
10. The flexible board product with large-surface electronic components according to claim 9, characterized in that Each soldering branch area comprises at least one protruding area, and each protruding area is arranged at one copper digging structure.