Manufacturing process of single-sided dense circuit high-thermal-conductivity copper substrate

Abstract

The invention discloses a manufacturing process of a single-sided dense circuit high-thermal-conductivity copper substrate, and relates to the technical field of circuit board processing, and the manufacturing process comprises the following operation steps: S1, cutting a copper substrate; s2, flatness detection is carried out; s3, browning the copper substrate; s4, high-conductivity glue pressing; and S5, subsequent manufacturing. According to the manufacturing process of the high-thermal-conductivity copper substrate with the single-sided dense lines, flatness detection is carried out twice in sequence, the overall flatness is detected for the first time, whether a concave surface which cannot be checked by naked eyes exists or not is detected for the second time, and under the condition that the detection is passed and a plate surface and a high-thermal-conductivity adhesive bonding surface are clean and free of sundries, the overall flatness is detected; the copper substrate and the high-conductivity glue are bonded and pressed, so that the problem that the dielectric layer is damaged due to fine particles or concave-convex surfaces in the machining process is avoided, the copper substrate is subjected to paper wrapping or glue pasting protection in the whole process when the copper substrate is turned over among the working procedures, external fine particles are prevented from being adsorbed, and the final forming quality of a product is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of circuit board processing, and in particular to a manufacturing process of a single-sided densely-circuited high-thermal-conductivity copper substrate. Background Art

[0002] As the name implies, the single-sided dense circuit high thermal conductivity copper substrate means that the wires are concentrated on one side of the high thermal conductivity copper substrate. The thermal conductivity of the copper substrate is much better than that of the aluminum substrate and the paste substrate. Therefore, the copper substrate is also called a high thermal conductivity copper substrate. The high thermal conductivity copper substrate mainly solves the thermal resistance of the product light-emitting body through an ultra-thin dielectric layer, and quickly conducts the heat generated by the light-emitting body. The thickness of the dielectric layer is generally within 100 microns, and the thinner the dielectric layer, the more stringent the production requirements during the product processing.

[0003] The existing single-sided densely-circuited high-thermal-conductivity copper substrate is affected by the thin dielectric layer during the manufacturing process. It is easily affected by fine particles during the processing, resulting in damage to the dielectric layer after pressing, which in turn causes poor quality such as short circuits between the product's conductive circuits and the substrate in subsequent processes, thus causing the product to be scrapped. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a manufacturing process for a single-sided densely-circuited high-thermal-conductivity copper substrate, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention is implemented by the following technical scheme: a manufacturing process of a single-sided densely-circuited high-thermal-conductivity copper substrate, the manufacturing process comprising the following steps: S1. Cutting of copper substrate: Use cutting equipment to cut out the copper substrate of the required size, and then use grinding equipment to grind one side of the copper substrate to eliminate uneven areas. After grinding, observe whether the grinding surface is clean, whether there are bumps, and whether there are small particles or debris; S2. Flatness detection: Place the polished surface of the copper substrate on a flat table, press one corner of the copper substrate, and use the measuring equipment to obtain the warping height of the diagonal. If the warping height is greater than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the flatness is not enough and needs to be re-grinded. If the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the grinding is qualified. S3, Browning of copper substrate: Browning the surface of the copper substrate with a browning liquid to roughen the surface of the copper substrate to increase the bonding area; S4, High Conductivity Adhesive Lamination: The grinding surface of the copper substrate is brought into contact with the bonding surface of the high-conductivity adhesive, so that the copper substrate and the high-conductivity adhesive are stacked, and the stacked materials are pressed together so that the high-conductivity adhesive and the copper substrate are fastened together; S5. Subsequent production: After the high-conductivity adhesive is pressed together with the copper substrate, it goes through the pattern transfer process, etching inspection, and solder mask processing process in sequence until it passes the final inspection to obtain the finished product.

[0006] Furthermore, in the step S1, when grinding the copper substrate, it is first tightened and the surface to be ground is exposed, and a plurality of balls are embedded in a ring shape around the copper substrate, and the top surface of the balls is consistent with the thickness of the copper substrate after grinding. Then, a grinding disc is attached to the surface of the copper substrate for grinding until the grinding disc contacts the balls. At this time, the balls rotate in place due to friction, which does not delay the grinding operation of the grinding disc and prevents the copper substrate from becoming thinner due to excessive grinding of the grinding disc.

[0007] Furthermore, in the step S2, if the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, further flatness testing is required to prevent concave areas on the polished surface.

[0008] Furthermore, the further flatness detection includes the following steps: The grinding surface of the copper substrate is placed upward in the box body, the box body and the copper substrate fit tightly together, and the hydrophobic film is adsorbed to the grinding surface of the copper substrate by vacuum adsorption, and then a scraper is inserted close to one side of the inner wall of the box body. The surface of the scraper is a hydrophobic structure, and the bottom of the scraper is attached to the surface of the copper substrate, that is, the surface of the hydrophobic film. Water is injected on one side of the scraper, and the scraper is moved. The scraper moves along the surface of the hydrophobic film. If water moves to the other side of the scraper during the movement, it means that the surface of the copper substrate has a concave area. If the water does not move to the other side of the scraper, it means that the surface of the copper substrate is flat.

[0009] Furthermore, in the step S4, the high-conductivity adhesive is a high-thermal conductivity adhesive.

[0010] Furthermore, in the step S4, before the high-conductivity adhesive is bonded to the polished surface of the copper substrate, it is necessary to confirm that the bonding surface of the high-conductivity adhesive is clean and free of cracks and small particles.

[0011] Furthermore, in the step S4, the high-conductivity adhesive is the dielectric layer.

[0012] Furthermore, in the step S4, the thickness of the high-conductivity adhesive is 50 microns.

[0013] Furthermore, in the steps S1-S5, the copper substrate needs to be wrapped with paper or glue for protection during the entire process when it is circulated in each process.

[0014] The present invention provides a manufacturing process for a single-sided densely-circuited high-thermal-conductivity copper substrate, which has the following beneficial effects: The manufacturing process of the single-sided dense circuit high thermal conductivity copper substrate uses a 50-micron thick high-conductivity adhesive dielectric layer to quickly conduct the heat generated by the product's light source, and two flatness tests are carried out in succession. The first test is for overall flatness, and the second test is for concave surfaces that are invisible to the naked eye. If the test passes, the copper substrate is bonded and pressed with the high-conductivity adhesive while ensuring that the board surface and the high-conductivity adhesive bonding surface are clean and free of debris, thereby avoiding damage to the dielectric layer caused by fine particles or uneven surfaces during the processing. The copper substrate is fully wrapped with paper or glue for protection during the turnover between each process to prevent the adsorption of fine external particles, thereby ensuring the quality of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The present invention is a schematic diagram of the overall process of manufacturing a single-sided densely-circuited high-thermal-conductivity copper substrate. Implementation

[0016] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0017] like Figure 1 As shown, the present invention provides a technical solution: a manufacturing process of a single-sided densely-circuited high-thermal-conductivity copper substrate, the manufacturing process comprising the following steps: S1. Cutting of copper substrate: Use cutting equipment to cut out the copper substrate of the required size, and then use grinding equipment to grind one side of the copper substrate to eliminate uneven areas. After grinding, observe whether the grinding surface is clean, whether there are bumps, and whether there are small particles or debris; Among them, when grinding the copper substrate, it is first tightened and the surface to be ground is exposed, and a number of balls are embedded in the periphery of the copper substrate in a ring shape, and the top surface of the balls is consistent with the thickness of the copper substrate after grinding. Then, a grinding disc is attached to the surface of the copper substrate for grinding until the grinding disc contacts the balls. At this time, the balls rotate in place due to friction, which does not delay the grinding operation of the grinding disc and prevents the copper substrate from becoming thinner due to excessive grinding of the grinding disc. S2. Flatness detection: Place the polished surface of the copper substrate on a flat table, press one corner of the copper substrate, and use the measuring equipment to obtain the warping height of the diagonal. If the warping height is greater than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the flatness is not enough and needs to be re-grinded. If the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the grinding is qualified. Among them, if the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, further flatness testing is required to prevent concave areas on the polished surface; Further flatness testing includes the following steps: The copper substrate is placed in the box body with the grinding surface facing upwards. The box body and the copper substrate fit tightly together. The hydrophobic film is adsorbed to the grinding surface of the copper substrate by vacuum adsorption. Then a scraper is inserted close to one side of the inner wall of the box body. The scraper surface is a hydrophobic structure, and the bottom of the scraper is attached to the surface of the copper substrate, that is, the surface of the hydrophobic film. Water is poured on one side of the scraper, and the scraper is moved. The scraper moves along the surface of the hydrophobic film. If water moves to the other side of the scraper during the movement, it means that the surface of the copper substrate has a concave area. If the water does not move to the other side of the scraper, it means that the surface of the copper substrate is flat. Two flatness tests are carried out successively. The first one tests the overall flatness, and the second one tests whether there are concave surfaces that cannot be detected by the naked eye. This avoids the problem of dielectric layer damage caused by uneven board surface or concave areas that cannot be detected by the naked eye. S3, Browning of copper substrate: Browning the surface of the copper substrate with a browning liquid to roughen the surface of the copper substrate to increase the bonding area; S4, High Conductivity Adhesive Lamination: The grinding surface of the copper substrate is brought into contact with the bonding surface of the high-conductivity adhesive, so that the copper substrate and the high-conductivity adhesive are stacked, and the stacked materials are pressed together so that the high-conductivity adhesive and the copper substrate are fastened together; Among them, the high-conductivity adhesive is a high-thermal conductivity adhesive. Before bonding the high-conductivity adhesive to the polished surface of the copper substrate, it is necessary to confirm that the bonding surface of the high-conductivity adhesive is clean and has no cracks and small particles. The high-conductivity adhesive is the dielectric layer. The thickness of the high-conductivity adhesive is 50 microns. The heat generated by the product light-emitting body is quickly conducted through the 50-micron-thick high-conductivity adhesive dielectric layer; S5. Subsequent production: After the high-conductivity adhesive is pressed together with the copper substrate, it goes through the pattern transfer process, etching inspection, and solder mask processing process in sequence until it passes the final inspection to obtain the finished product; In the above steps S1-S5, the copper substrate needs to be wrapped with paper or glue for protection during the entire process when it is circulated in each process to prevent the adsorption of small external particles.

[0018] In summary, if Figure 1 As shown in the figure, the manufacturing process of the single-sided dense circuit high thermal conductivity copper substrate is to first use a cutting device to cut out the copper substrate of the required size, and then use a grinding device to grind one side of the copper substrate to eliminate uneven areas. After grinding, observe whether the grinding surface is clean, whether there are bumps, and whether there are small particles or debris; Among them, when grinding the copper substrate, it is first tightened and the surface to be ground is exposed, and a number of balls are embedded in the periphery of the copper substrate in a ring shape, and the top surface of the balls is consistent with the thickness of the copper substrate after grinding. Then, a grinding disc is attached to the surface of the copper substrate for grinding until the grinding disc contacts the balls. At this time, the balls rotate in place due to friction, which does not delay the grinding operation of the grinding disc and prevents the copper substrate from becoming thinner due to excessive grinding of the grinding disc. Then place the polished surface of the copper substrate on a flat table, press one corner of the copper substrate, and use the measuring equipment to obtain the warping height of the diagonal. If the warping height is greater than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the flatness is not enough and needs to be re-grinded. If the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the grinding is qualified. Among them, if the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, further flatness testing is required to prevent concave areas on the polished surface; Further flatness testing includes the following steps: The copper substrate is placed in the box body with the grinding surface facing upwards. The box body and the copper substrate fit tightly together. The hydrophobic film is adsorbed to the grinding surface of the copper substrate by vacuum adsorption. Then a scraper is inserted close to one side of the inner wall of the box body. The scraper surface is a hydrophobic structure, and the bottom of the scraper is attached to the surface of the copper substrate, that is, the surface of the hydrophobic film. Water is poured on one side of the scraper, and the scraper is moved. The scraper moves along the surface of the hydrophobic film. If water moves to the other side of the scraper during the movement, it means that the surface of the copper substrate has a concave area. If the water does not move to the other side of the scraper, it means that the surface of the copper substrate is flat. Two flatness tests are carried out successively. The first one tests the overall flatness, and the second one tests whether there are concave surfaces that cannot be detected by the naked eye. This avoids the problem of dielectric layer damage caused by uneven board surface or concave areas that cannot be detected by the naked eye. Then, the surface of the copper substrate is browned with a browning liquid to roughen the surface of the copper substrate to increase the bonding area; Then, the grinding surface of the copper substrate is brought into contact with the bonding surface of the high-conductivity adhesive, so that the copper substrate and the high-conductivity adhesive are stacked, and the stacked materials are pressed together so that the high-conductivity adhesive and the copper substrate are fastened together; Among them, the high-conductivity adhesive is a high-thermal conductivity adhesive. Before bonding the high-conductivity adhesive to the polished surface of the copper substrate, it is necessary to confirm that the bonding surface of the high-conductivity adhesive is clean and has no cracks and small particles. The high-conductivity adhesive is the dielectric layer. The thickness of the high-conductivity adhesive is 50 microns. The heat generated by the product light-emitting body is quickly conducted through the 50-micron-thick high-conductivity adhesive dielectric layer; After the high-conductivity adhesive is pressed together with the copper substrate, it goes through the pattern transfer process, etching inspection, and solder mask processing process in sequence until it passes the final inspection to obtain the finished product; During the above production process, the copper substrate needs to be wrapped with paper or glue for protection during the entire process when it is circulated in each process to prevent the adsorption of small external particles.

[0019] The embodiments of the present invention are given for the purpose of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. A manufacturing process for a single-sided densely-circuited high thermal conductivity copper substrate, characterized in that: The manufacturing process comprises the following steps: S1. Cutting of copper substrate: Use cutting equipment to cut out the copper substrate of the required size, and then use grinding equipment to grind one side of the copper substrate to eliminate uneven areas. After grinding, observe whether the grinding surface is clean, whether there are bumps, and whether there are small particles or debris; S2. Flatness detection: Place the polished surface of the copper substrate on a flat table, press one corner of the copper substrate, and use the measuring equipment to obtain the warping height of the diagonal. If the warping height is greater than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the flatness is not enough and needs to be re-grinded. If the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, it means that the grinding is qualified. S3, Browning of Copper Substrate: Browning the surface of the copper substrate with a browning liquid to roughen the surface of the copper substrate to increase the bonding area; S4, High Conductivity Adhesive Lamination: The grinding surface of the copper substrate is brought into contact with the bonding surface of the high-conductivity adhesive, so that the copper substrate and the high-conductivity adhesive are stacked, and the stacked materials are pressed together so that the high-conductivity adhesive and the copper substrate are fastened together; S5. Subsequent production: After the high-conductivity adhesive is pressed together with the copper substrate, it goes through the pattern transfer process, etching inspection, and solder mask processing process in sequence until it passes the final inspection to obtain the finished product.

2. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the step S1, when grinding the copper substrate, it is first tightened and the surface to be ground is exposed, and a plurality of balls are embedded in the periphery of the copper substrate in a ring shape, and the top surface of the balls is consistent with the thickness of the copper substrate after grinding. Then, a grinding disc is attached to the surface of the copper substrate for grinding until the grinding disc contacts the balls. At this time, the balls rotate in place due to friction, which does not delay the grinding operation of the grinding disc and prevents the copper substrate from becoming thinner due to excessive grinding of the grinding disc.

3. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the step S2, if the warping height is less than 7.5 thousandths of the total diagonal length of the copper substrate, further flatness testing is required to prevent the polishing surface from having concave areas.

4. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 3, characterized in that: The further flatness detection comprises the following steps: The grinding surface of the copper substrate is placed upward in the box body, the box body and the copper substrate fit tightly together, and the hydrophobic film is adsorbed to the grinding surface of the copper substrate by vacuum adsorption, and then a scraper is inserted close to one side of the inner wall of the box body. The surface of the scraper is a hydrophobic structure, and the bottom of the scraper is attached to the surface of the copper substrate, that is, the surface of the hydrophobic film. Water is injected on one side of the scraper, and the scraper is moved. The scraper moves along the surface of the hydrophobic film. If water moves to the other side of the scraper during the movement, it means that the surface of the copper substrate has a concave area. If the water does not move to the other side of the scraper, it means that the surface of the copper substrate is flat.

5. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the step S4, the high-conductivity adhesive is a high-thermal-conductivity adhesive.

6. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the step S4, before the high-conductivity adhesive is bonded to the polished surface of the copper substrate, it is necessary to confirm that the bonding surface of the high-conductivity adhesive is clean and free of cracks and small particles.

7. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the step S4, the high-conductivity adhesive is the dielectric layer.

8. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the step S4, the thickness of the high-conductivity adhesive is 50 microns.

9. The manufacturing process of a single-sided densely-circuited high thermal conductivity copper substrate according to claim 1, characterized in that: In the steps S1-S5, the copper substrate needs to be wrapped with paper or glue for protection during the entire process.

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