Circuit board and processing method thereof

Abstract

The invention provides a circuit board and a processing method thereof, and relates to the technical field of circuit boards, the circuit board provided by the invention comprises a substrate, a transmission line and a golden finger, and the transmission line and the golden finger are both arranged on the substrate; one end of the golden finger is electrically connected with one end of the transmission line along the extension direction of the golden finger; the substrate is provided with slotted holes, and the slotted holes are distributed on at least one side of the golden fingers along the extending direction crossed with the golden fingers. According to the circuit board provided by the invention, reflection and loss in a signal transmission process can be reduced, and signal transmission requirements are met; the circuit board processing method provided by the invention has the advantage of being easy to implement.

Description

Technical Field

[0001] The present application relates to the technical field of circuit boards, and in particular to a circuit board and a processing method thereof. Background Art

[0002] With the rapid development of electronic information technology, the demand for high-speed digitalization and wireless communication is increasing, which has promoted the advancement of high-speed printed circuit technology.

[0003] In existing high-speed circuit board products, in order to facilitate the connection between the gold finger and the external signal line, the width of the gold finger is generally made wider than the width of the transmission line, and the overall impedance at the gold finger position is smaller than the overall impedance at the transmission line position.

[0004] However, when the external signal passes through the gold finger and the transmission line in sequence, the impedance discontinuity between the gold finger and the transmission line will cause reflection and loss of the signal during the transmission process, thus failing to meet the signal transmission requirements. Summary of the Invention

[0005] In view of the above problems, the present application provides a circuit board and a processing method thereof. The circuit board provided by the present application can reduce reflection and loss of signals during transmission and meet the signal transmission requirements; and the processing method of the circuit board provided by the present application has the advantage of being easy to implement.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] In a first aspect, the present application provides a circuit board, comprising a substrate, a transmission line, and a gold finger, wherein the transmission line and the gold finger are both arranged on the substrate; along the extension direction of the gold finger, one end of the gold finger is electrically connected to one end of the transmission line;

[0008] The substrate is provided with slots, which are distributed on at least one side of the golden finger along an extending direction intersecting the golden finger.

[0009] The beneficial effects of the present application are as follows: the slot can reduce the comprehensive dielectric constant around the gold finger, thereby increasing the impedance at the gold finger position, so that the overall impedance at the gold finger position tends to be consistent with the overall impedance at the transmission line position, thereby improving impedance continuity, thereby reducing reflection, loss, crosstalk and other problems in the signal transmission process, and meeting the signal transmission requirements.

[0010] In a possible implementation, there are multiple transmission lines and multiple gold fingers, and the multiple transmission lines and the multiple gold fingers are electrically connected in a one-to-one correspondence;

[0011] Along the extending direction perpendicular to the gold fingers, a plurality of gold fingers are arranged at intervals; a slot is provided between two adjacent gold fingers.

[0012] In this way, two adjacent gold fingers can share the slot, and the slot can simultaneously reduce the comprehensive dielectric constant around the two adjacent gold fingers.

[0013] In a possible implementation, there are multiple slots located between two adjacent gold fingers, and the multiple slots are spaced apart along the extending direction of the gold fingers.

[0014] In this way, the impedance at the gold finger position is further improved, so that the overall impedance at the gold finger position is more matched with the overall impedance at the transmission line position.

[0015] In a possible implementation, the plurality of slots located between two adjacent gold fingers are arranged at equal intervals along the extension direction of the gold fingers.

[0016] In this way, after the multiple slots are arranged at equal intervals along the extension direction of the gold finger, the impedance of different positions of the gold finger can be improved more evenly, further meeting the signal transmission requirements.

[0017] In a possible implementation, a slot is provided between two adjacent gold fingers; along the extension direction of the gold finger, the gold finger has a first end and a second end that are oppositely arranged, and the transmission line is electrically connected to the first end;

[0018] One end of the slot extends toward the first end, and the other end extends toward the second end.

[0019] In this way, the extended length of the slot can be adapted to the extended length of the gold finger, so that the overall impedance at the gold finger position is more matched with the overall impedance at the transmission line position.

[0020] In a possible implementation, the slot is a through hole, or the slot is a blind hole.

[0021] In this way, the depth of the blind hole can be designed according to the actual impedance requirement. When the depth of the blind hole is designed to be greater, the impedance of the blind hole to the gold finger position will be improved more.

[0022] In a possible implementation, the slot is filled with a dielectric material; and the impedance of the substrate at the slot is smaller than the impedance of the dielectric material.

[0023] In this way, the presence of dielectric material can reduce the comprehensive dielectric constant around the gold finger, thereby increasing the impedance at the gold finger position.

[0024] In one possible implementation, the dielectric material fills the entire slot;

[0025] Alternatively, the dielectric material fills a portion of the slot.

[0026] In this way, the filling volume of the dielectric material can be designed according to the actual impedance requirements.

[0027] A second aspect of the present application provides a method for processing a circuit board, comprising:

[0028] Providing a substrate, on which a transmission line and a gold finger are arranged, wherein along the extension direction of the gold finger, one end of the gold finger is electrically connected to one end of the transmission line;

[0029] Slots are processed on the substrate, and the slots are distributed on at least one side of the gold finger along an extending direction intersecting the gold finger.

[0030] In a possible implementation, after the slots are machined on the substrate, the method further includes:

[0031] Detect the diameter and depth of the slot holes.

[0032] In this way, after the aperture and depth of the slot are detected, the processing quality of the circuit board can be guaranteed.

[0033] The present application provides slots next to the gold finger. The slots can reduce the comprehensive dielectric constant around the gold finger, thereby increasing the overall impedance at the gold finger position, so that the overall impedance at the gold finger position tends to be consistent with the overall impedance at the transmission line position, and improving impedance continuity. Therefore, when the signal passes through the gold finger and the transmission line in sequence, the circuit board provided by the present application can reduce a series of problems that affect signal integrity, such as reflection, loss, and crosstalk, during the signal transmission process, thereby meeting the signal transmission requirements. In addition, the processing method of the circuit board provided by the present application has the advantage of being easy to implement, facilitating the increase of the impedance at the gold finger position, so that the overall impedance at the gold finger position tends to be consistent with the overall impedance at the transmission line position, thereby better meeting the signal transmission requirements.

[0034] The structure of the present application and its other inventive objectives and beneficial effects will be more clearly understood through the description of specific embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0036] Figure 1 It is a three-dimensional diagram of a circuit board in the prior art;

[0037] Figure 2 A three-dimensional diagram of a circuit board provided in an embodiment of the present application;

[0038] Figure 3 A partial top view of a circuit board provided in an embodiment of the present application;

[0039] Figure 4 for Figure 3 Cross-sectional view at AA in the middle;

[0040] Figure 5 for Figure 3 Cross-sectional view at the middle BB;

[0041] Figure 6 For Figure 4 The corresponding another view;

[0042] Figure 7 For Figure 5 The corresponding another view;

[0043] Figure 8 For Figure 5 Another corresponding view;

[0044] Figure 9 This is the impedance-time relationship diagram measured in the experiment;

[0045] Figure 10 This is the insertion loss-frequency relationship diagram measured in the experiment;

[0046] Figure 11 A flowchart of a method for processing a circuit board provided in an embodiment of the present application.

[0047] Description of reference numerals:

[0048] 100-substrate;

[0049] 110-slot;

[0050] 200-transmission line;

[0051] 300-Golden Finger;

[0052] 310-first end;

[0053] 320-second end;

[0054] 400-dielectric material;

[0055] 500-metallized vias;

[0056] 600-chip;

[0057] 700- components;

[0058] 800-Connection area. DETAILED DESCRIPTION

[0059] With the rapid development of electronic information technology, the demand for high-speed digitalization and wireless communications is increasing, which has promoted the advancement of high-speed printed circuit technology and has become more stringent in the requirements for signal integrity. In related technologies, precise matching impedance control and packaging technology can be used to ensure signal integrity. Among them, impedance consistency is of great significance for ensuring the signal quality of high-speed products, ensuring signal timing and reducing crosstalk noise.

[0060] like Figure 1 As shown in the figure, a three-dimensional diagram of a circuit board in the prior art is shown. In the existing circuit board products, the transmission line 200 on the substrate 100 is electrically connected to the gold finger 300 in the connection area 800. In order to facilitate the connection between the gold finger 300 and the external signal line, the width of the gold finger 300 is often designed to be wider than the width of the transmission line 200. As a result, the overall impedance at the gold finger 300 position will be smaller than the overall impedance at the transmission line 200 position.

[0061] Since the overall impedance at the gold finger position is smaller than the overall impedance at the transmission line position, when the external signal can pass through the gold finger and the transmission line in sequence, the impedance discontinuity between the gold finger and the transmission line will cause reflection and loss of the signal during the transmission process, thereby failing to meet the signal transmission requirements.

[0062] Based on the above-mentioned problems, the present application provides a circuit board and a processing method thereof, wherein the circuit board includes a substrate, a transmission line, and a gold finger, wherein the transmission line and the gold finger are both arranged on the substrate; along the extension direction of the gold finger, one end of the gold finger is electrically connected to one end of the transmission line; and slots are provided on the substrate, and along the extension direction intersecting the gold finger, the slots are distributed on at least one side of the gold finger. The present application provides slots next to the gold finger. The presence of the slots can reduce the comprehensive dielectric constant around the gold finger, thereby improving the overall impedance at the gold finger position, so that the overall impedance at the gold finger position tends to be consistent with the overall impedance at the transmission line position, improving impedance continuity, thereby reducing signal reflection and loss, and meeting signal transmission requirements.

[0063] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0064] The following specific embodiments are used to describe in detail the technical solution of the present application and how the technical solution of the present application solves the above technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0065] The following combination Figures 2 to 9 , the structure of the circuit board provided in the embodiment of the present application is described in detail.

[0066] like Figure 2 and Figure 3 As shown, the circuit board provided by the present application includes a substrate 100, a transmission line 200, and a gold finger 300, wherein the transmission line 200 and the gold finger 300 are both arranged on the substrate 100; along the extension direction of the gold finger 300, one end of the gold finger 300 is electrically connected to one end of the transmission line 200; in addition, the external signal line can be electrically connected to the other end of the gold finger 300, so that the signal can pass through the external signal line, the gold finger 300, and the transmission line 200 in sequence, and then input into the internal circuit of the circuit board. In addition, the electrically connected gold finger 300 and the transmission line 200 can be made of the same material; along the transmission direction perpendicular to the signal, the cross-section of the gold finger 300 is larger than the cross-section of the transmission line 200.

[0067] In addition, if Figure 2 and Figure 3 As shown, in the circuit board provided by the present application, the substrate 100 is provided with slots 110, which are distributed on at least one side of the gold finger 300 along a direction intersecting the extension of the gold finger 300. Specifically, the slots 110 can be distributed on at least one side of the gold finger 300 along a direction perpendicular to the extension of the gold finger 300. For example, the slots 110 can be distributed only on one side of the gold finger 300; or, the slots 110 can be distributed on both opposite sides of the gold finger 300; or, some number of gold fingers 300 can have slots 110 on both opposite sides, while another number of gold fingers 300 can have slots 110 on only one side.

[0068] Therefore, the present application sets a slot 110 next to the gold finger 300. The presence of the slot 110 can reduce the comprehensive dielectric constant around the gold finger 300, thereby increasing the impedance at the gold finger 300 position, so that the overall impedance at the gold finger 300 position tends to be consistent with the overall impedance at the transmission line 200 position, thereby improving impedance continuity; therefore, when the signal passes through the gold finger 300 and the transmission line 200 in sequence, the presence of the slot and the circuit board provided by the present application can reduce a series of problems affecting signal integrity such as reflection, loss and crosstalk during signal transmission, thereby meeting signal transmission requirements.

[0069] It should be noted that the slots 110 in this application can be air holes. Specifically, the slots 110 can be prepared by drilling air holes. Alternatively, the slots 110 can be filled with a high-impedance dielectric material 400. Thus, this application achieves impedance optimization by changing the comprehensive dielectric constant around the gold finger 300, so that the overall impedance at the gold finger 300 position can better match the overall impedance at the transmission line 200 position on the circuit board, thereby reducing reflection, loss, and crosstalk during high-speed signal transmission.

[0070] Figure 9 The impedance-time relationship diagram measured in the experiment is shown. Figure 10 The insertion loss-frequency relationship graph measured in the experiment is shown in the figure. Figure 9 As shown, compared with not processing air holes on the substrate 100, after processing air holes on the substrate 100 in the present application, the air holes can increase the impedance at the position of the gold finger 300. In addition, as Figure 10 As shown, compared with not processing air holes on the substrate 100, after the air holes are processed on the substrate 100 in the present application, the loss of high-speed signals during the transmission process is reduced.

[0071] In a specific embodiment, Figures 3 to 6 As shown, multiple transmission lines 200 and multiple gold fingers 300 are provided, with the multiple transmission lines 200 and multiple gold fingers 300 being electrically connected in a one-to-one correspondence. Furthermore, the multiple gold fingers 300 are spaced apart along a direction perpendicular to the extension of the gold fingers 300, and a slot 110 is provided between two adjacent gold fingers 300. This arrangement allows the slot 110 to be shared between two adjacent gold fingers 300, thereby simultaneously reducing the overall dielectric constant around the two adjacent gold fingers 300. Furthermore, the number of slots 110 required and the processing time are reduced, and the overall space occupied by the slots 110 on the circuit board is reduced, thereby making the circuit board structure more streamlined.

[0072] For example, when a plurality of gold fingers 300 are arranged at intervals, a slot 110 is provided between two adjacent gold fingers 300; Figure 3 As shown, the gold fingers 300 located at both ends of the spaced arrangement direction among the multiple gold fingers 300 may have slots 110 distributed on only one side; or, the gold fingers 300 located at both ends of the spaced arrangement direction among the multiple gold fingers 300 may have slots 110 distributed on both opposite sides.

[0073] Further, such as Figure 3 and Figure 4As shown, multiple slots 110 are provided between two adjacent gold fingers 300, and the slots 110 are spaced apart along the extension direction of the gold fingers 300. This arrangement, in which the slots 110 are spaced apart along the extension direction of the gold fingers 300, can further improve the impedance at the gold fingers 300, thereby better matching the overall impedance at the gold fingers 300 with the overall impedance at the transmission line 200.

[0074] Specifically, among the plurality of slots 110 spaced apart along the extension direction of the gold finger 300, the positions of the slots 110 at both ends of the extension direction are adapted to the positions of the ends of the gold finger 300. Figure 3 As shown, the lengths of different gold fingers 300 can be kept different. When a slot 110 is provided between two adjacent gold fingers 300 of different lengths, among the multiple slots 110 spaced apart along the extension direction of the gold fingers 300, the slots 110 at both ends of the extension direction are positioned closer to the ends of the gold finger 300 with a longer length. Furthermore, the overall arrangement length of the multiple slots 110 spaced apart can be consistent with the length of the gold finger 300 with a longer length.

[0075] Specifically, such as Figure 3 and Figure 4 As shown, multiple slots 110 located between two adjacent gold fingers 300 are spaced evenly along the extension direction of the gold fingers 300. This arrangement, in which the multiple slots 110 are spaced evenly along the extension direction of the gold fingers 300, can make the impedance at different locations of the gold fingers 300 more uniform, further meeting signal transmission requirements.

[0076] Specifically, when a slot 110 is provided between two adjacent gold fingers 300 , the spacing between the slot 110 and the two adjacent gold fingers 300 may be kept consistent.

[0077] In another specific embodiment, Figure 6As shown, a slot 110 is provided between two adjacent gold fingers 300. Along the extension direction of the gold fingers 300, the gold fingers 300 have a first end 310 and a second end 320 that are oppositely disposed. The transmission line 200 is electrically connected to the first end 310. One end of the slot 110 extends toward the first end 310, and the other end extends toward the second end 320. This arrangement facilitates machining of the slot 110 by providing only one elongated slot 110 between two adjacent gold fingers 300. The slot 110 extends with one end toward the first end 310 and the other end toward the second end 320, further improving the impedance at the gold fingers 300, ensuring a better match between the overall impedance at the gold fingers 300 and the overall impedance at the transmission line 200. Specifically, when the elongated slot 110 is provided between two adjacent gold fingers 300 of different lengths, the overall extension length of the slot 110 can be consistent with the length of the longer gold finger 300.

[0078] For example, Figure 4 and Figure 5 As shown, the slot 110 can be a through hole; in this case, the slot 110 can maximize the impedance at the position of the gold finger 300.

[0079] For example, Figure 6 As shown, the slot 110 may also be a blind hole. It should be noted that the depth of the blind hole can be designed according to the actual impedance requirement. When the depth of the blind hole is designed to be greater, the blind hole will increase the impedance of the gold finger 300 position to a greater extent.

[0080] In the embodiments of this application, Figure 7 and Figure 8 As shown, slot 110 is filled with dielectric material 400; the impedance of substrate 100 at slot 110 is lower than the impedance of dielectric material 400. This arrangement reduces the overall dielectric constant around gold finger 300, thereby increasing the impedance at gold finger 300, bringing the overall impedance at gold finger 300 closer to that of transmission line 200. Furthermore, the impedance of dielectric material 400 can be greater than that of air, further improving the impedance at gold finger 300 and meeting signal transmission requirements.

[0081] For example, Figure 7 As shown, the dielectric material 400 may fill the entire slot 110; in addition, as shown Figure 8As shown, dielectric material 400 can partially fill slot 110. It should be noted that the filling volume of dielectric material 400 can be designed based on actual impedance requirements. When the impedance of dielectric material 400 is greater than that of air, a larger filling volume of dielectric material 400 will increase the impedance at the location of gold finger 300. When the impedance of dielectric material 400 is less than that of air, a smaller filling volume of dielectric material 400 will increase the impedance at the location of gold finger 300.

[0082] In addition, the present invention also provides a method for processing a circuit board. Figure 11 As shown, the processing method of the circuit board includes:

[0083] S100: providing a substrate, on which a transmission line and a gold finger are arranged, and along an extension direction of the gold finger, one end of the gold finger is electrically connected to one end of the transmission line.

[0084] Specifically, the end of the gold finger 300 facing away from the transmission line 200 can be electrically connected to an external signal line, and the end of the transmission line 200 facing away from the gold finger 300 can be electrically connected to one of the metallized via 500, the chip 600, and the component 700. Thus, the signal can sequentially pass through the external signal line, the gold finger 300, and the transmission line 200, and ultimately be transmitted to one of the metallized via 500, the chip 600, and the component 700. Specifically, the outer layer pattern can be processed on the substrate 100 according to the normal multi-layer printed circuit processing flow, and the transmission line 200 and gold finger 300 can be formed.

[0085] S200: Processing slots on the substrate, wherein the slots are distributed on at least one side of the gold finger along an extension direction intersecting the gold finger.

[0086] Specifically, the slots 110 can be distributed on at least one side of the gold finger 300 along a direction perpendicular to the extension direction of the gold finger 300. The slots 110 can be distributed only on one side of the gold finger 300; alternatively, the slots 110 can be distributed on both opposite sides of the gold finger 300; alternatively, the slots 110 can be distributed on both opposite sides of a portion of the gold fingers 300, while the slots 110 can be distributed on only one side of another portion of the gold fingers 300.

[0087] Specifically, the slot hole 110 may be machined by a mechanical drilling or controlled deep milling method, or the slot hole 110 may be machined by a laser processing method.

[0088] Furthermore, after slot 110 is machined on substrate 100, the process also includes testing the diameter and depth of slot 110. If the diameter and depth of slot 110 meet the requirements, the product is qualified. It should be noted that when designing a circuit board, the diameter and depth of slot 110 can be designed based on actual needs. The larger the diameter and depth of slot 110, the greater the improvement in impedance at the location of gold finger 300.

[0089] Furthermore, after laser processing is performed to form slots 110 on substrate 100, the process also includes cleaning the laser holes from resin residue and debris left behind by the laser burn, thereby ensuring the cleanliness of the circuit board. Furthermore, after laser processing is performed to form slots 110 on substrate 100, solder mask can be printed on the surface of substrate 100, and the post-processing process can be completed.

[0090] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to a fixed connection, an indirect connection via an intermediate medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0091] In this application, or by implication, the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting this application. In the description of this application, the meaning of "plurality" is two or more, unless otherwise precisely and specifically specified.

[0092] The terms "first," "second," "third," "fourth," etc. (if any) in the specification and claims of the present application and in the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential sequence. It should be understood that the numbers used in this way are interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products, or apparatus.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A circuit board, characterized in that: The device comprises a substrate, a transmission line and a gold finger, wherein the transmission line and the gold finger are both arranged on the substrate; along the extension direction of the gold finger, one end of the gold finger is electrically connected to one end of the transmission line; The substrate is provided with slots, which are distributed on at least one side of the gold finger along an extending direction intersecting the gold finger.

2. The circuit board according to claim 1, wherein: There are multiple transmission lines and multiple gold fingers, and the multiple transmission lines and the multiple gold fingers are electrically connected in a one-to-one correspondence; Along an extending direction perpendicular to the gold fingers, a plurality of the gold fingers are arranged at intervals; and the slot is provided between two adjacent gold fingers.

3. The circuit board according to claim 2, characterized in that There are a plurality of slots located between two adjacent gold fingers, and the plurality of slots are spaced apart along the extending direction of the gold fingers.

4. The circuit board according to claim 3, characterized in that The plurality of slots located between two adjacent gold fingers are arranged at equal intervals along the extending direction of the gold fingers.

5. The circuit board according to claim 2, wherein: The slot is provided between two adjacent gold fingers; along the extension direction of the gold finger, the gold finger has a first end and a second end that are oppositely arranged, and the transmission line is electrically connected to the first end; One end of the slot extends toward the first end, and the other end extends toward the second end.

6. The circuit board according to any one of claims 1 to 5, characterized in that: The slot is a through hole, or the slot is a blind hole.

7. The circuit board according to any one of claims 1 to 5, characterized in that: The slot is filled with a dielectric material; the impedance of the substrate at the slot is smaller than the impedance of the dielectric material.

8. The circuit board according to claim 7, characterized in that: The dielectric material fills all the slots; Alternatively, the dielectric material fills a portion of the slot.

9. A method for processing a circuit board, characterized in that: include: Providing a substrate, on which a transmission line and a gold finger are provided, wherein along an extension direction of the gold finger, one end of the gold finger is electrically connected to one end of the transmission line; Slots are processed on the substrate, and are distributed on at least one side of the gold finger along an extension direction intersecting the gold finger.

10. The method for processing a circuit board according to claim 9, wherein: After the slots are formed on the substrate, the method further includes: The aperture and depth of the slot are detected.

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