Golden finger etching method and circuit board
By setting up etching blocks during the gold finger etching process, evenly etching around the gold finger, the problems of uneven and deformation of the gold finger etching are solved, and uniform etching and shape stability of the gold finger are achieved.
Patent Information
- Application Number
- CN202411563604.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-04
- Publication Date
- 2025-03-14
AI Technical Summary
During the gold finger etching process, due to the different shapes and spacings of gold fingers designed by different customers, the degree of exchange between the etching potion and copper foil is inconsistent, resulting in uneven etching of the gold fingers, which may lead to deformation.
By stacking dry film and copper foil on the substrate in turn, forming a circuit board, and placing a film on the circuit board for exposure, transferring the target pattern and removing the dry film, appearing the copper foil, and adding etching blocks during the etching process to evenly etch the surroundings of the gold fingers.
By setting up the etching block, the degree of attack of the gold fingers by the etching potion is consistent, ensuring that the gold fingers do not deform after etching, achieving uniform etching of the gold fingers.
Smart Images
Figure CN119629882A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of gold finger etching, in particular to a gold finger etching method and a circuit board. Background Art
[0002] Goldfinger is one of the important parts that connect PCB board with other electronic devices. It is mainly responsible for transmitting signals and power to ensure the normal operation of electronic devices. When making goldfinger, acid solution is often used to etch copper foil. In the process of making goldfinger, due to the different shapes of goldfinger designed by different customers, the spacing around the fingers will also be different. Therefore, the amount of etching solution used is also different, which will lead to inconsistent exchange between solution and copper foil at all times, resulting in the goldfinger not being etched evenly. Summary of the invention
[0003] The embodiment of the present invention provides a gold finger etching method and a circuit board to solve the problem of uneven etching during the gold finger etching process.
[0004] The first aspect of the present application provides a gold finger etching method, comprising: A laser drilling machine is used to drill holes in the substrate, and copper is plated at the drilling positions of the substrate, so that the dry film and the copper foil are sequentially superimposed and pressed on the substrate to form a circuit board; Placing a film board on the circuit board, and exposing the circuit board after the film board is placed, so as to transfer the target pattern on the film board to the circuit board, wherein the target pattern on the film board includes a gold finger design pattern and an etch block design pattern; Removing the film plate placed on the circuit board to reveal the dry film of the unexposed part of the circuit board; Removing the dry film on the unexposed portion of the circuit board to reveal the copper foil on the unexposed portion of the circuit board; The unexposed copper foil of the circuit board is etched according to the target pattern to form a gold finger and an etching block, wherein the etching solution added during the etching process will etch the surrounding of the gold finger, and the etching block makes the surrounding of the gold finger attacked by the etching solution to the same extent, ensuring that the gold finger is not deformed after etching; After the etching of the circuit board is completed, the dry film on the exposed part of the circuit board is removed.
[0005] Optionally, the erosion block is designed with different sizes based on different distances between two gold fingers.
[0006] Optionally, the unexposed copper foil of the circuit board is etched according to the target pattern to form a gold finger and an etched block, including: The circuit board is covered with an acidic etching solution, and the acidic etching solution etches the unexposed copper foil of the circuit board according to the target pattern, and forms gold fingers and accompanying etching blocks after etching.
[0007] Optionally, exposing the circuit board after placing the film board to transfer the target pattern on the film board to the circuit board includes: Irradiating the circuit board with the film plate placed thereon with ultraviolet rays; The circuit board after the film board is placed is irradiated with ultraviolet rays, which will leave the target pattern on the film board on the circuit board.
[0008] Optionally, removing the dry film on the unexposed portion of the circuit board comprises: A weak acid solution is used to cover the circuit board to remove the dry film on the unexposed portion of the circuit board.
[0009] Optionally, removing the dry film on the exposed portion of the circuit board includes: The circuit board is covered with an alkaline solution to remove the dry film on the exposed portion of the circuit board.
[0010] Optionally, the circuit board is covered with an alkaline solution to remove the dry film on the exposed portion of the circuit board, and then the method includes: The circuit board is cleaned and dried to remove the alkaline solution covering the circuit board.
[0011] Optionally, the dry film and the copper foil are sequentially laminated and then pressed on a substrate to form a circuit board, which includes: The copper foil is polished and dust on the polished copper foil is removed so as to press the dry film on the copper foil to form a circuit board.
[0012] A second aspect of the present application provides a circuit board, the circuit board comprising a gold finger, and the gold finger is prepared by using any of the above-mentioned gold finger etching methods.
[0013] The above-mentioned gold finger etching method and circuit board are formed by sequentially stacking a dry film and a copper foil and then pressing them on a substrate; placing a film board on the circuit board, and exposing the circuit board after placing the film board to transfer the target pattern on the film board to the circuit board, wherein the target pattern on the film board includes a gold finger design pattern and an etch block design pattern; removing the film board placed on the circuit board to reveal the dry film of the unexposed part of the circuit board; removing the dry film of the unexposed part of the circuit board to reveal the copper foil of the unexposed part of the circuit board; etching the copper foil of the unexposed part of the circuit board according to the target pattern to form a gold finger and an etch block, wherein the etching solution added during the etching process will etch the surrounding of the gold finger, and the etch block makes the surrounding of the gold finger attacked by the etching solution to the same extent, ensuring that the gold finger is not deformed after etching; after the etching of the circuit board is completed, removing the dry film of the exposed part of the circuit board. The present application arranges an etching block at a location with a large spacing between two gold fingers when designing the gold fingers, thereby ensuring that the distance between the etching block and the two gold fingers is relatively consistent, reducing the rate of exchange between the etching solution and the copper foil, and ensuring that the extent to which the surrounding areas of the gold fingers are attacked by the etching solution is consistent, thereby ensuring that the gold fingers are not deformed after etching. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.
[0015] Figure 1 is a flow chart of a gold finger etching method according to an embodiment of the present invention; Figure 2 This is a diagram showing the effect of a gold finger etching method in one embodiment of the present invention. DETAILED DESCRIPTION
[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0017] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.
[0018] It should also be understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.
[0019] As used in the present specification and the appended claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]", depending on the context.
[0020] In addition, in the description of the present specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.
[0021] References to "one embodiment" or "some embodiments" etc. described in the present specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.
[0022] It should be understood that the order of execution of the steps in the following embodiments does not imply a precedence of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
[0023] In order to illustrate the technical solution of the present invention, specific embodiments are provided below for illustration.
[0024] In one embodiment, if Figure 1 As shown, a gold finger etching method is provided, which specifically includes the following steps: S10: laminating the dry film and the copper foil in sequence and pressing them on the substrate to form a circuit board; S20: placing a film board on the circuit board, and exposing the circuit board after the film board is placed, so as to transfer the target pattern on the film board to the circuit board, wherein the target pattern on the film board includes a gold finger design pattern and an etch block design pattern; S30: removing the film sheet placed on the circuit board to reveal the dry film on the unexposed portion of the circuit board; S40: removing the dry film on the unexposed portion of the circuit board to reveal the copper foil on the unexposed portion of the circuit board; Specifically, in the embodiment of the present application, copper foil and dry film are sequentially pressed on the substrate, and after the dry film is pressed, a circuit board is formed, wherein the circuit board is punched on the substrate using a laser drilling machine, and the substrate is electroplated with copper, and the punched position of the substrate is copper plated, so that a conductive layer is formed in the hole to facilitate the dry film and copper foil to be sequentially superimposed and pressed on the electroplated substrate to form a circuit board. A film board containing the customer's gold finger pattern and the etched block design pattern is placed on the circuit board, and after ultraviolet exposure and development and other process flows, the gold finger design pattern and the etched block design pattern on the film board can be transferred to the circuit board. After the gold finger design pattern and the etched block design pattern on the film board are transferred to the circuit board, the film board is removed, and the dry film of the part that has not been exposed to ultraviolet light can be revealed. By adding a developer, the dry film of the unexposed part of the circuit board can be removed, and the exposed part of the dry film will be left on the circuit board. After adding the developer, the gold finger design pattern and the etched block design pattern can be seen more clearly on the circuit board. Since the dry film of the unexposed part has been removed, the copper foil of the unexposed part of the circuit board will be exposed. Wherein, the circuit board is covered with a weak acid solution to remove the dry film of the unexposed part of the circuit board. Wherein, the exposure is to place a film negative and irradiate it with ultraviolet light, so that the dry film of the ultraviolet irradiated part will polymerize and become an anti-corrosion layer. The development refers to dissolving and washing away the dry film of the part not irradiated by ultraviolet light to expose the copper foil there.
[0025] Optionally, as an embodiment of the present application, after the dry film and the copper foil are stacked in sequence and pressed onto a substrate to form a circuit board, the copper foil needs to be polished and the dust on the copper foil after polishing needs to be removed so that the dry film can be pressed onto the copper foil to form a circuit board.
[0026] S50: etching the unexposed copper foil of the circuit board according to the target pattern to form a gold finger and an etching block, wherein the etching solution added during the etching process will etch the surrounding of the gold finger, and the etching block makes the surrounding of the gold finger attacked by the etching solution to the same extent, ensuring that the gold finger is not deformed after etching; S60: After the etching of the circuit board is completed, the dry film on the exposed part of the circuit board is removed.
[0027] Specifically, since the dry film on the part exposed by ultraviolet rays will form an anti-corrosion layer to protect the exposed copper foil, and the dry film on the part that has not been exposed has been removed using a developer, revealing the copper foil on the part that has not been exposed. At this time, the copper foil on the part that has not been exposed is not protected by the anti-corrosion layer. Therefore, pouring acidic etching solution on the circuit board will corrode the copper foil on the part that has not been exposed until gold fingers and accompanying etching blocks are formed. After the etching of the circuit board is completed, the dry film on the exposed part of the circuit board is removed. Since a chemical reaction will occur between the accompanying etching blocks and the etching solution for exchange, the accompanying etching blocks will eventually be completely corroded, leaving only the gold fingers designed by the customer.
[0028] Optionally, as an embodiment of the present application, removing the dry film on the exposed portion of the circuit board includes: The circuit board is covered with an alkaline solution to remove the dry film on the exposed part of the circuit board. After the dry film on the exposed part of the circuit board is removed with the alkaline solution, the circuit board needs to be cleaned and dried to remove the alkaline solution covering the circuit board.
[0029] In this embodiment, if Figure 2 As shown, in the process of pouring the etching solution to form the gold finger, the acid etching solution will attack the surrounding of the gold finger. When the etching solution attacks the surrounding of the gold finger, due to the irregular shape of the gold finger, the exchange between the etching solution and the copper foil is small in the part with a smaller distance between the two gold fingers, and deformation will not occur. However, in the part with a larger distance between the two gold fingers, the exchange degree of the solution becomes stronger due to the larger distance between the gold fingers, which will accelerate the etching of the copper foil by the etching solution, and the gold finger formed at this time will be deformed. Therefore, when designing the gold finger, an etchant block is set at the place where the distance between the two gold fingers is larger, to ensure that the distance between the etchant block and the two gold fingers is relatively consistent, to reduce the rate of exchange between the etching solution and the copper foil, to ensure that the surrounding of the gold finger is attacked by the etching solution to a consistent degree, thereby ensuring that the gold finger is not deformed after etching.
[0030] As an optional embodiment, different sizes of the erosion block are designed based on the different spacings between the two gold fingers of the erosion block, specifically including: It is necessary to first design the gold finger design pattern on the film board according to the gold finger design pattern required by the customer. After the gold finger design pattern is designed on the film board, calculate the distance between the two gold finger design patterns. If the maximum spacing between the two gold finger design patterns is less than or equal to 17μm, then design a 10μm*10μm erosion block between the maximum spacing of the two gold finger design patterns. If the maximum spacing between the two gold finger design patterns is greater than 17μm and less than 34μm, then design a 25μm*25μm erosion block between the maximum spacing of the two gold finger design patterns. If the maximum spacing between the two gold finger design patterns is greater than 34μm, then design a 38μm*38μm erosion block between the maximum spacing of the two gold finger design patterns. After obtaining the size of the etch block according to the maximum spacing between the two gold finger design patterns, the etch block design pattern is added between the gold finger design patterns or next to the gold finger design pattern, and the gold finger design pattern and the etch block design pattern are transferred to the circuit board through the film plate. After development and etching, gold fingers and etch blocks are formed. Due to the chemical reaction between the etch block and the etching solution, the etch block is finally completely etched away, leaving only the gold fingers designed by the customer.
[0031] In this embodiment, the distance between the gold fingers is calculated to determine the size of the etched block between the two gold fingers, so that etched blocks of different sizes can be designed according to the different distances between the gold fingers, thereby ensuring that the gold fingers will not be deformed after etching.
[0032] In one embodiment, a gold finger etching method is provided, such as step S20, that is, exposing the circuit board after placing the film board to transfer the target pattern on the film board to the circuit board, specifically comprising the following steps: S21: irradiating the circuit board after the film board is placed with ultraviolet rays; S22: The circuit board after the film board is placed is irradiated with ultraviolet rays, and the target pattern on the film board is left on the circuit board.
[0033] Specifically, after the dry film is pressed, a circuit board is formed, and a film board containing the customer's gold finger pattern and etched block design pattern is placed on the circuit board. After exposure to ultraviolet light and development and other process flows, the gold finger design pattern and etched block design pattern on the film board can be transferred to the circuit board.
[0034] In this embodiment, the target pattern on the film is transferred to the circuit board by ultraviolet irradiation, and the target pattern is formed on the circuit board, so that the gold finger is easily etched according to the designed target pattern.
[0035] In this embodiment, the above-mentioned gold finger etching method and circuit board are formed by sequentially stacking a dry film and a copper foil and then pressing them on a substrate; placing a film board on the circuit board, and exposing the circuit board after placing the film board to transfer the target pattern on the film board to the circuit board, wherein the target pattern on the film board includes a gold finger design pattern and an etch block design pattern; removing the film board placed on the circuit board to reveal the dry film of the unexposed part of the circuit board; removing the dry film of the unexposed part of the circuit board to reveal the copper foil of the unexposed part of the circuit board; etching the copper foil of the unexposed part of the circuit board according to the target pattern to form a gold finger and an etch block, wherein the etching solution added during the etching process will etch the surrounding of the gold finger, and the etch block makes the surrounding of the gold finger attacked by the etching solution to the same extent, ensuring that the gold finger is not deformed after etching; after the etching of the circuit board is completed, the dry film of the exposed part of the circuit board is removed.
[0036] In the embodiment of the present application, when designing the gold finger, the present application sets an etching block at a place where the spacing between the two gold fingers is larger, ensures that the distance between the etching block and the two gold fingers is relatively consistent, reduces the exchange rate between the etching solution and the copper foil, and ensures that the degree of attack by the etching solution around the gold finger is consistent, thereby ensuring that the gold finger is not deformed after etching.
[0037] In an embodiment of the present application, a circuit board is also provided, the circuit board comprising a gold finger, which is prepared by the gold finger etching method mentioned in any of the above embodiments. The gold finger etching method can also be used in manufacturing electronic components or PCB substrates.
[0038] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.
Claims
1. A gold finger etching method, characterized in that: include: A laser drilling machine is used to drill holes in the substrate, and copper is plated at the drilling positions of the substrate, so that the dry film and the copper foil are sequentially superimposed and pressed on the substrate to form a circuit board; Placing a film board on the circuit board, and exposing the circuit board after the film board is placed, so as to transfer the target pattern on the film board to the circuit board, wherein the target pattern on the film board includes a gold finger design pattern and an etch block design pattern; Removing the film plate placed on the circuit board to reveal the dry film of the unexposed part of the circuit board; Removing the dry film on the unexposed portion of the circuit board to reveal the copper foil on the unexposed portion of the circuit board; The unexposed copper foil of the circuit board is etched according to the target pattern to form a gold finger and an etching block, wherein the etching solution added during the etching process will etch the surrounding of the gold finger, and the etching block makes the surrounding of the gold finger attacked by the etching solution to the same extent, ensuring that the gold finger is not deformed after etching; After the etching of the circuit board is completed, the dry film on the exposed part of the circuit board is removed.
2. The gold finger etching method according to claim 1, characterized in that: The erosion block is designed with different sizes based on the different distances between the two gold fingers.
3. The gold finger etching method according to claim 1, characterized in that: The unexposed copper foil of the circuit board is etched according to the target pattern to form a gold finger and an etched block, including: The circuit board is covered with an acidic etching solution, and the unexposed copper foil of the circuit board is etched according to the target pattern, and gold fingers and accompanying etching blocks are formed after etching.
4. The gold finger etching method according to claim 1, characterized in that: Exposing the circuit board after placing the film board to transfer the target pattern on the film board to the circuit board, including: Irradiating the circuit board with the film plate placed thereon with ultraviolet rays; The circuit board after the film board is placed is irradiated with ultraviolet rays, which will leave the target pattern on the film board on the circuit board.
5. The gold finger etching method according to claim 1, characterized in that: Removing the dry film on the unexposed portion of the circuit board includes: A weak acid solution is used to cover the circuit board to remove the dry film on the unexposed portion of the circuit board.
6. The gold finger etching method according to claim 1, characterized in that: The method of removing the dry film on the exposed part of the circuit board comprises: The circuit board is covered with an alkaline solution to remove the dry film on the exposed portion of the circuit board.
7. The gold finger etching method according to claim 1, characterized in that: The dry film and copper foil are laminated and pressed on the substrate to form a circuit board, which includes: The copper foil is polished and dust on the polished copper foil is removed so as to press the dry film on the copper foil to form a circuit board.
8. The gold finger etching method according to claim 6, characterized in that: The circuit board is covered with an alkaline solution to remove the dry film on the exposed part of the circuit board, and then includes: The circuit board is cleaned and dried to remove the alkaline solution covering the circuit board.
9. The gold finger etching method according to claim 6, characterized in that: Performing exposure and development processing on the circuit board to transfer the target pattern to the circuit board, including: The circuit board is irradiated with ultraviolet rays, and after being irradiated with the ultraviolet rays, the circuit board is cleaned with an acid solution to transfer the target pattern to the circuit board.
10. A circuit board, comprising a gold finger, wherein the gold finger is prepared by the gold finger etching method according to any one of claims 1 to 9.