Manufacturing method of aluminum substrate with high-reliability surface identification

Abstract

The invention discloses a method for manufacturing an aluminum substrate with high-reliability surface identification, which comprises the following steps of: manufacturing a first blue glue layer for a circuit layer, manufacturing a first dry film pattern for an aluminum plate layer, performing acid etching and electroplating on the aluminum plate layer, and manufacturing a second blue glue layer; tearing off the first blue glue layer, manufacturing a second dry film pattern on the circuit layer, manufacturing a surface circuit pattern, removing the second dry film pattern, and then manufacturing a solder mask pattern; tearing off the second blue glue layer, performing nickel gold immersion, and removing the first dry film pattern to form a circuit board; the mode of forming the groove through chemical etching and then depositing the nickel-gold deposition layer is adopted to replace the processing mode of directly manufacturing ink characters or printing the characters by laser after aluminum surface oxidation in the prior art, the durable surface identification is formed by utilizing the corrosion resistance of the metal layer, the reliability and the identification degree of the characters are greatly improved, and the character quality is improved. The whole process can be realized by using a processing process of a traditional circuit board, and a cross-field and cross-industry processing process is not needed, so that the processing efficiency is greatly improved, and the processing difficulty is reduced.

Description

Technical Field

[0001] The invention relates to the field of aluminum substrate manufacturing, and in particular to a method for manufacturing an aluminum substrate with high-reliability surface marking. Background Art

[0002] Aluminum substrates have good heat dissipation and high strength. With the development of LED, automobile and other fields, the requirements for high precision and high reliability of surface marking processing are becoming higher and higher.

[0003] For the surface marking of this type of aluminum-based aluminum substrate, the existing production methods and main problems are: (1) The surface of the aluminum substrate is screen-printed with black or white text ink, which is then baked and cured to form a surface mark. However, since the surface of the aluminum substrate is relatively smooth and easily oxidized, this method also has defects such as unclear characters, natural oxidation of the surface, and poor corrosion resistance.

[0004] (2) The surface of the aluminum substrate is treated with black oxidation, and then laser engraving and ablation are used to make surface markings. However, since the black oxidation process of the aluminum surface is relatively complicated and the processing flow is relatively long, and it does not fall within the processing scope of the traditional aluminum substrate in this field and industry, it will incur high processing costs and increase environmental pollution. Furthermore, in subsequent applications, the black oxidized aluminum surface is susceptible to environmental corrosion or is affected by factors such as collision and friction, which can easily cause problems such as character shedding and character blurring.

[0005] Therefore, in order to solve the above-mentioned problems, it is necessary to provide a method for manufacturing an aluminum substrate with a high-reliability surface mark. Summary of the invention

[0006] The present invention aims to solve the comprehensive problems of low processing accuracy and low reliability in the surface marking of aluminum substrates produced by the prior art, and proposes a method for producing an aluminum substrate with a high-reliability surface marking, wherein the upper and lower surfaces of the aluminum substrate are respectively a circuit layer and an aluminum plate layer, and the production method comprises the following steps: S10: forming a first blue glue layer on the circuit layer, pasting a first dry film on the aluminum plate layer, and forming a first dry film pattern, so that the whole plate forms a dry film pattern plate.

[0007] S20: etching the aluminum plate layer of the dry film graphic board to form an etched board, electroplating it, and making a second blue glue layer, so that the whole board forms a blue glue board.

[0008] S30: tear off the first blue glue layer, stick a second dry film on the circuit layer, make a second dry film pattern, make a surface circuit pattern, then remove the second dry film pattern, and then make a solder mask pattern to form a solder mask on the whole board.

[0009] S40: tear off the second blue glue layer, perform nickel-gold deposition, and remove the first dry film pattern to form the aluminum substrate.

[0010] Furthermore, the first blue glue layer is prepared by attaching a blue glue film or screen printing blue glue ink.

[0011] Furthermore, the etching is acid etching.

[0012] Furthermore, after the etching, the etching plate is baked for the first time.

[0013] Furthermore, the temperature of the first baking is 60° C. to 75° C., and the time of the first baking is 10 min to 30 min.

[0014] Furthermore, the etching depth is 3 μm to 20 μm.

[0015] Furthermore, the step of tearing off the second blue glue layer includes: baking the blue glue layer for a second time, and then tearing off the second blue glue layer.

[0016] Furthermore, the temperature of the second baking is 60° C. to 75° C., and the time of the second baking is 3 min to 10 min.

[0017] Furthermore, the removing of the first dry film pattern is: soaking in a NaOH solution or a KOH solution with a mass fraction of 1.5% to 3% for 5 minutes to 10 minutes, and then removing the film with a film removing liquid.

[0018] Furthermore, the removing of the first dry film pattern includes grinding away the first dry film pattern by grinding.

[0019] The technical solution of the present invention adopts the method of chemical etching to form groove electroplating and then depositing the nickel-gold layer, replacing the existing method of directly making ink characters or laser marking characters after aluminum surface oxidation, and using the corrosion resistance of the metal layer to form a durable surface mark, which greatly improves the reliability and recognition of the characters. In the processing process, the copper circuit on the surface of the aluminum substrate is first made, and then the circuit pattern on the other side is made, and finally nickel-gold is deposited at the same time, avoiding the secondary nickel-gold deposition method of "single-sided→single-sided". The processing flow can be effectively shortened, the processing accuracy of double-sided nickel-gold deposition is improved, the high-risk, harmful and toxic processes of nickel-gold deposition are reduced, and environmental protection is improved; the overall process can be realized using the processing flow of traditional aluminum substrates, without the need for processing flows across the field and industry, which greatly improves the processing efficiency and relatively reduces the processing difficulty, providing an efficient, environmentally friendly and cost-effective solution, improving the reliability, clarity and durability of the surface mark of the aluminum substrate, and reducing the risk of fading or wear of the surface mark in long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0021] Figure 1 Schematic diagram of the process flow of an embodiment of the present invention; Figure 2 A schematic plan view of a dry film graphic plate according to an embodiment of the present invention; Figure 3 A schematic plan view of an etching plate according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the planar structure of a blue plastic board according to an embodiment of the present invention; Figure 5 Schematic diagram of the planar structure of a dry film plate according to an embodiment of the present invention; Figure 6 Schematic diagram of the planar structure of a solder mask according to an embodiment of the present invention; Figure 7 Schematic diagram of the planar structure of an aluminum substrate according to an embodiment of the present invention.

[0022] Description of Figure Numbers: 10-dry film graphic board; 1010-circuit layer; 1020-aluminum plate layer; 1030-insulating layer; 1040-first blue glue layer; 1050-first dry film graphic; 20-etched board; 2010-etched graphic; 30-blue glue board; 3010-second blue glue layer; 3020-electroplated copper graphic; 40A-dry film board; 4010-second dry film graphic; 40-solder mask board; 4020-surface circuit graphic; 4030-solder mask graphic; 50-aluminum substrate; 5010-pad graphic; 5020-surface identification.

[0023] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0024] 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 only 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.

[0025] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, inside, outside...) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0026] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0027] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0028] See also Figure 1 , Figure 1 It is a schematic diagram of the process flow of an embodiment of the present invention.

[0029] The manufacturing process of the embodiment of the present invention includes using Figure 1 The following will implement the various steps in the process Figure 1 Each step in the process is further explained step by step.

[0030] The upper and lower surfaces of the aluminum substrate of this embodiment are respectively a circuit layer 1010 and an aluminum plate layer 1020 , and the middle layer is an insulating layer 1030 .

[0031] See also Figure 2 , Figure 2 Schematic diagram of a dry film graphic plate according to an embodiment of the present invention.

[0032] S10: forming a first blue glue layer 1040 on the circuit layer 1010, and pasting a first dry film on the aluminum plate layer 1020 to form a first dry film pattern 1050, and forming a dry film pattern plate 10 on the whole plate.

[0033] The first blue glue layer 1040 is formed on the circuit layer 1010 to provide temporary protection for the circuit layer 1010 in the subsequent processing steps so that it will not be affected by the subsequent processing process and provide a processing basis for the subsequent etching and electroplating processing. The first dry film pattern 1050 is formed on the aluminum plate layer 1020 to form a processing basis for the electroplated copper pattern 3020 in the subsequent process.

[0034] Optionally, the first blue glue layer 1040 is made by attaching a blue glue film or screen printing blue glue ink. Screen printing generally uses a screen with a mesh size of 71, 100 or 120, preferably 71 mesh. The thickness of the screen printing blue glue ink can be selected from 20μm to 50μm, preferably 35μm or 50μm.

[0035] See also Figure 3 and Figure 4 , Figure 3 A schematic plan view of an etching plate according to an embodiment of the present invention; Figure 4 It is a schematic diagram of the planar structure of the blue plastic board according to the embodiment of the present invention.

[0036] S20: etching the aluminum plate layer 1020 of the dry film pattern plate 10 to form an etching pattern 2010, forming an etching plate 20 on the whole plate, and then electroplating and making a second blue glue layer 3010, forming a blue glue plate 30 on the whole plate.

[0037] Electroplating forms an electroplated copper pattern 3020, which provides a copper layer pattern basis for the subsequent further production of nickel-gold and improves the adhesion of nickel-gold. The thickness of the electroplated copper pattern 3020 can be 5μm to 20μm. It is not necessary to electroplating too thick, otherwise the problem of raised surface mark 5020 will occur.

[0038] The aluminum plate layer 1020 not covered by the first dry film pattern 1050 is selectively removed by using an acidic chemical reagent to form the pattern of the desired surface identification 5020, which is the graphic basis for post-processing. This is one of the key steps to achieve the surface identification 5020. This step requires precise control of etching time and temperature to ensure an ideal etching effect.

[0039] Furthermore, the etching depth is 3μm to 20μm. The appropriate etching depth can ensure that the surface mark 5020 has sufficient visual contrast and will not cause structural damage to the aluminum substrate 50. At the same time, the concave-convex structure formed by etching helps to improve the adhesion of the metal layer material, and cooperates with the electroplating in the subsequent process. By depositing a metal layer on the pattern surface of the surface mark 5020 formed by etching, the surface mark 5020 is not easily erased or worn, can maintain a good condition for a long time in harsh environments, and has high reliability.

[0040] It is worth noting that acid etching is preferably used for etching the aluminum plate layer 1020 of the dry film graphic board 10. Generally, an acid etching solution of a H2O2 mixed with HCl system is selected. The acid etching line processing of the aluminum substrate 50 can be selected to complete the acid etching process. The concentration of the acid etching solution is low, and it is not easy to cause passivation on the surface of the aluminum plate layer 1020.

[0041] Acid etching and alkaline etching can also be combined, that is, acid etching is first used to prevent surface passivation caused by etching and remove the passivation that may occur on the surface, and then a slight alkaline etching is performed to better remove the surface passivation and oxide layer, providing conductive and resistant surface conditions for subsequent copper electroplating; alkaline etching can be processed using an alkaline etching line for an aluminum substrate 50, and the general solution components are a mixed system of components such as cupric chloride, ammonium bicarbonate, ammonia water, and water; multiple etchings require control of the etching amount, as well as the impact of the etching process on the blue glue layer and the dry film layer.

[0042] Optionally, after etching, the etching plate 20 is baked for the first time.

[0043] Furthermore, the temperature of the first baking is 60° C. to 75° C., and the time of the first baking is 10 min to 30 min.

[0044] The first baking is performed to remove excess moisture and stabilize the oxide film layer, so that the first dry film pattern 1050 is completely solidified on the surface. On the one hand, it provides a processing basis for the subsequent electroplating process. On the other hand, it provides a board surface basis for the subsequent production of the second blue glue layer 3010 on the first dry film pattern 1050 and then tearing off the second blue glue layer 3010, thereby preventing the first dry film pattern 1050 from being torn when the second blue glue layer 3010 is torn off.

[0045] It is worth mentioning that the step of making the second blue glue layer 3010 can also be replaced by sticking a dry film, but it will cause a large number of subsequent repeated exposure, development, film removal, and re-sticking of the dry film, resulting in a cumbersome process, high processing cost, and low processing precision. Therefore, this embodiment adopts a method of directly making the second blue glue layer 3010 on the first dry film pattern 1050, and covering and protecting the first dry film pattern 1050, the aluminum plate layer 1020, and the electroplated copper pattern 3020. On the one hand, it effectively improves the processing efficiency, and on the other hand, it avoids secondary sticking, secondary exposure, and secondary development, which may easily cause the development pattern and the electroplated copper pattern 3020 to be offset from each other, affecting the precision of subsequent nickel-gold plating and other processing. That is, the first dry film pattern 1050 and the nickel-gold plating processing in the subsequent process all use the same layer of dry film, and there is no problem of low processing precision caused by secondary pattern production.

[0046] The second blue glue layer 3010 can also be made by attaching a blue glue film or silk-screening blue glue ink. Silk-screen printing generally uses a screen with a mesh size of 71, 100 or 120, preferably 71 mesh. The thickness of the silk-screen blue glue ink can be selected from 20μm to 50μm, preferably 35μm or 50μm.

[0047] See also Figure 5 and Figure 6 , Figure 5Schematic diagram of the planar structure of a dry film plate according to an embodiment of the present invention; Figure 6 Schematic diagram of the planar structure of the solder mask according to the embodiment of the present invention.

[0048] S30: tear off the first blue glue layer 1040, stick a second dry film on the circuit layer 1010 and make a second dry film pattern 4010, form a dry film board 40A on the whole board, then make a surface circuit pattern 4020, remove the second dry film pattern 4010, and then make a solder resist pattern 4030, and form a solder resist board 40 on the whole board.

[0049] The first blue glue layer 1040 is torn off to expose the underlying circuit layer 1010 , and the surface circuit pattern 4020 and the solder resist pattern 4030 are produced according to the standard of the original design data, providing accurate position positioning for the final pad pattern 5010 .

[0050] See also Figure 7 , Figure 7 Schematic diagram of the planar structure of an aluminum substrate according to an embodiment of the present invention.

[0051] S40 : tear off the second blue glue layer 3010 , perform nickel-gold deposition, and remove the first dry film pattern 1050 to form an aluminum substrate 50 .

[0052] The second blue glue layer 3010 serving as a temporary protective layer is torn off to expose the electroplated copper pattern 3020, and the entire board is subjected to nickel-gold plating treatment, so that the pad pattern 5010 and the electroplated copper pattern 3020 are processed with nickel-gold plating at the same time, thereby avoiding the complex process of processing in batches and the process of using double materials, and avoiding the problem of misalignment caused by separate nickel-gold plating.

[0053] The nickel-gold immersion simultaneously forms a protective layer with good wear resistance and corrosion resistance on the surface of the pad pattern 5010 and the electroplated copper pattern 3020, protecting the copper surface from oxidation, ensuring the quality and long-term stability of the welding point, and enabling the electroplated copper pattern 3020 to achieve pattern metallization to form the required surface mark 5020.

[0054] Optionally, the second blue glue layer 3010 is to be torn off by baking the second blue glue layer 3010 for a second time, and then to tear off the second blue glue layer 3010. By heating the second blue glue layer 3010 again, the physical properties of the material of the second blue glue layer 3010 can be changed, so that the glue layer can be softened and easier to peel off, thereby preventing the first dry film pattern 1050 from being pulled off when tearing off the second blue glue layer 3010 and reducing the possibility of residue.

[0055] Furthermore, the temperature of the second baking is 60°C to 75°C, and the time of the second baking is 3min to 10min, ensuring that the second blue glue layer 3010 can be fully softened without affecting the electroplated copper pattern 3020 below. The control of baking temperature and time helps to avoid deformation or damage caused by excessive temperature, and can effectively shorten the subsequent processing time.

[0056] It is worth noting that after the second blue glue layer 3010 is baked for the second time, it is preferably torn off in time within 5 minutes or less; because the second blue glue layer 3010 is easy to peel off due to the change of physical properties after the heating treatment, if the second blue glue layer 3010 is removed after cooling, the viscosity of the second blue glue layer 3010 may increase again, forming a negative effect, making it more difficult to completely remove it from the surface of the aluminum substrate 50, and may leave residues or damage the logo. Therefore, it is torn off in time after baking to ensure that the aluminum substrate 50 and the electroplated copper pattern 3020 will not be damaged due to excessive temperature, and the second blue glue layer 3010 will not harden again due to waiting time.

[0057] Optionally, the first dry film pattern 1050 is removed by soaking in a NaOH solution or a KOH solution with a mass fraction of 1.5% to 3% for 5 minutes to 10 minutes, and then removing the film using a film remover.

[0058] Since the first dry film pattern 1050 is completely cured in the early stage, it may be difficult to remove the dry film if a film stripping liquid is used to directly remove the film. Therefore, the first dry film pattern 1050 can be effectively removed by soaking in a strong alkali diluted solution and then using a film stripping liquid to remove the film.

[0059] In this embodiment, the first dry film pattern 1050 is immersed in a NaOH or KOH solution with a mass fraction of 1.5% to 3%, thereby forming selective corrosion and dissolving the first dry film pattern 1050, but it will not significantly affect the aluminum substrate 50 itself. After the alkaline solution treatment is completed, the film stripping liquid is used for treatment to completely remove the remaining first dry film pattern 1050 material and ensure that the surface of the aluminum substrate 50 is clean and tidy without damaging the already formed surface mark 5020.

[0060] Optionally, removing the first dry film pattern 1050 is: grinding off the first dry film pattern 1050 by grinding; preferably, grinding with an abrasive belt, and further preferably: grinding once with an 800-mesh abrasive belt and then grinding once with a 1200-mesh abrasive belt.

[0061] In order to avoid the influence of alkaline solution immersion and film stripping by film stripping liquid on the solder mask pattern 4030, the first dry film pattern 1050 can be removed by grinding. Since the hardness of the board itself is relatively high, the hardness of the first dry film pattern 1050 is relatively small, so a larger grit sanding belt can be used for grinding.

[0062] This embodiment uses chemical etching to form grooves and then deposits a nickel-gold layer, replacing the existing processing method of directly making ink characters or laser marking characters after oxidation of the aluminum surface, and uses the corrosion resistance of the metal layer to form a durable surface mark 5020, which greatly improves the reliability and recognition of the characters. In the processing process, the surface copper circuit of the aluminum substrate 50 is first made, and then the circuit pattern on the other side is made, and finally both sides are nickel-gold-plated at the same time, avoiding the secondary nickel-gold-plated method of "single-sided→single-sided" production, which can effectively shorten the processing flow, reduce the use of high-risk, harmful and toxic processes of nickel-gold plating, and improve environmental protection. The overall process can be implemented using the processing flow of the traditional aluminum substrate 50, without the need for cross-field and cross-industry processing flows, greatly improving processing efficiency, relatively reducing processing difficulty, and providing an efficient, environmentally friendly and cost-effective solution, which improves the reliability, clarity and durability of the surface mark 5020 of the aluminum substrate 50, and reduces the risk of fading or wear of the surface mark 5020 during long-term use.

[0063] It is worth noting that due to the relatively precise design and processing of the aluminum substrate 50, the structure of the actual processing process and the thickness of each layer, line width and other dimensions are all at the micron level. If the drawings are made according to the enlarged ratio of the actual structure, the problem of unclear drawings will appear. Therefore, in order to more clearly and intuitively represent the implementation process of the manufacturing method of this embodiment, the drawings of this embodiment are all schematic diagrams that enlarge the technical features, which do not represent the size of the actual structure, nor are they enlarged drawings of the actual structure in proportion.

[0064] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for manufacturing an aluminum substrate with high reliability surface marking, wherein the upper and lower surfaces of the aluminum substrate are a circuit layer and an aluminum plate layer respectively, characterized in that: The production method comprises the following steps: S10: forming a first blue glue layer on the circuit layer, pasting a first dry film on the aluminum plate layer and forming a first dry film pattern, and forming a dry film pattern plate on the whole plate; S20: etching the aluminum plate layer of the dry film graphic plate to form an etched plate, electroplating it, and making a second blue glue layer, so that the whole plate forms a blue glue plate; S30: tearing off the first blue glue layer, attaching a second dry film to the circuit layer and making a second dry film pattern, making a surface circuit pattern, then removing the second dry film pattern, and then making a solder mask pattern, so that the whole board forms a solder mask; S40: tear off the second blue glue layer, perform nickel-gold deposition, and remove the first dry film pattern to form the aluminum substrate.

2. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 1, characterized in that: The first blue glue layer is prepared by attaching a blue glue film or screen printing blue glue ink.

3. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 1, characterized in that: The etching is acid etching.

4. A method for manufacturing an aluminum substrate with a high reliability surface mark as claimed in claim 1 or 3, characterized in that: After the etching is performed, the etched plate is baked for the first time.

5. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 4, characterized in that: The temperature of the first baking is 60° C. to 75° C., and the time of the first baking is 10 min to 30 min.

6. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 1, characterized in that: The etching depth is 3 μm to 20 μm.

7. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 1, characterized in that: The step of tearing off the second blue glue layer comprises: baking the blue glue layer for a second time, and then tearing off the second blue glue layer.

8. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 7, characterized in that: The temperature of the second baking is 60° C. to 75° C., and the time of the second baking is 3 min to 10 min.

9. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 1, characterized in that: The first dry film pattern is removed by soaking in a NaOH solution or a KOH solution with a mass fraction of 1.5% to 3% for 5 minutes to 10 minutes, and then removing the film with a film removing liquid.

10. The method for manufacturing an aluminum substrate with a high reliability surface mark according to claim 1, characterized in that: The removing of the first dry film pattern includes grinding away the first dry film pattern by grinding.

Images