A manufacturing process for 3D metal circuits

Abstract

This invention discloses a manufacturing process for 3D metal circuits, comprising the following steps: S1, designing a plastic carrier structure according to requirements; S2, designing and creating a molding die for the plastic carrier; S3, injection molding the plastic carrier using plastic material; S4, developing appropriate laser parameters for different plastic materials; S5, applying five-axis laser engraving technology, adjusting the parameters of different lasers to roughen and modify the plastic surface according to the properties of different plastics; S6, depositing a conductive material onto the roughened area of ​​the plastic carrier surface using a catalyst solution; S7, performing chemical electroplating on the surface of the plastic carrier to form a metal layer. Compared with existing technologies, this invention solves the problems of traditional processes requiring the addition of metal particles to the plastic; processing only on materials specified by LPKF, which are extremely expensive; the need to use LPKF's dedicated machines, resulting in high equipment costs; and limitations on the use of high-frequency (5G) technology.

Description

Technical Field

[0001] This invention relates to the field of metal circuit manufacturing, and more specifically to a manufacturing process for 3D metal circuits. Background Technology

[0002] my country has formed the world's largest electronic component industrial system in terms of production and sales scale, with a relatively complete range of categories and a basically complete industrial chain. However, the domestic electronic component industry currently suffers from shortcomings such as being large but not strong, lacking leading enterprises, and having weak basic capabilities. In particular, there is still a significant gap in many high-end and high-precision electronic components, especially in 3D metal circuit manufacturing technology, where it lags far behind developed countries.

[0003] The most mature existing metal circuit forming technology is the Laser Direct 3D Circuit Forming (LDS) technology, which is unique to LPKF in Germany. The three main process steps of laser direct forming include: injection molding, laser processing, and metallization of circuit patterns. Its technical feature is that metal particles are added to the plastic in advance, and then after molding, laser processing is applied to the planned circuit surface to activate the metal particles, and then chemical electroplating is applied to form the circuit. Although LDS process technology is currently the main method for making 3D circuits, it has many disadvantages, including: (1) material limitations: it can only be processed on materials specified by LPKF, and the material cost is extremely high (metal particles need to be added to the plastic first); (2) it requires the use of LPKF's special machines (special laser processing machines), and the equipment cost is high; (3) the use of metal particles added to the plastic substrate limits the use of high frequency (5G) technology; (4) the materials of the already developed structure have to be replaced, which increases the time for applying for safety regulations and certifications, increases costs, and lengthens the development process.

[0004] In view of this, the applicant conducted in-depth research on the above-mentioned issues, which led to this case. Summary of the Invention

[0005] The main objective of this invention is to provide a manufacturing process for 3D metal circuits, which solves the problems of traditional processes, such as the need to add metal particles to plastic first; the limitation of processing on materials specified by LPKF, which are extremely expensive; the need to use LPKF's dedicated machines, which are costly; and the limitation of high-frequency (5G) technology.

[0006] To achieve the above objectives, the solution of the present invention is:

[0007] A manufacturing process for 3D metal circuits includes the following steps:

[0008] S1. Design the plastic carrier structure according to requirements;

[0009] S2. Design and develop molding dies for plastic carriers;

[0010] S3. The plastic carrier is injection molded using plastic material;

[0011] S4. Develop and tailor laser parameters for different plastic materials;

[0012] S5. Applying five-axis laser engraving technology, by adjusting the parameters of different lasers, the surface of plastics is roughened and modified according to the properties of different plastics.

[0013] S6. A conductive material is deposited on the roughened area of ​​the plastic carrier surface using a catalyst solution;

[0014] S7. Perform chemical electroplating on the surface of the plastic carrier to form a metal layer.

[0015] Furthermore, the molding material of the plastic carrier includes PET, LCP, PPS, or bakelite.

[0016] Furthermore, the thickness of the metal layer is ≥18μm.

[0017] Furthermore, the catalyst may be a tin activator.

[0018] Furthermore, in S5, a five-axis laser engraving device is used to roughen and modify the plastic material. This five-axis laser engraving device includes a frame, an automatic feeding device, a laser engraving device, and a dust cover. The automatic feeding device includes a first track, a feeding column, a worktable, a lifting platform, a rotary table, and a drive motor. The feeding column is mounted on the frame, and its side wall has a feeding port. The first track is located outside the feeding port and has a first sliding gripper. The lower end of the rotary table has a connecting part, which is rotatably connected to the feeding column. The drive motor drives the connecting part. The rotating column and rotating table are rotated. The middle of the feeding column and rotating table are provided with a feeding channel. The lifting platform is located in the feeding channel and moves up and down. The rotating table is provided with guide arms that are evenly arranged along the circumference of the rotating table. The end of the guide arm is provided with a turntable that is rotatably connected. The guide arm is provided with a second track and a second sliding gripper. The turntable is provided with a third track and a third sliding gripper. The worktable is fixedly connected to the frame. The middle of the worktable is provided with a through hole. The dust cover is provided above the rotating table. The laser device is installed on the dust cover.

[0019] Furthermore, the lower end of the turntable is provided with a rotating shaft, which is rotatably connected to the guide arm. A first gear is provided on the rotating shaft, and an internal gear ring is provided on the worktable. The first gear is meshed with the internal gear ring.

[0020] Furthermore, the worktable is provided with an annular guide groove, and the lower end of the rotating shaft is provided with a guide cylinder that is slidably connected and embedded in the annular guide groove.

[0021] Furthermore, the feeding channel is provided with a lifting slide rail, the lifting platform is installed on the lifting slide rail, the upper surface of the lifting platform is provided with a positioning groove, and the two sides of the positioning groove are provided with clearance grooves.

[0022] Furthermore, the dust cover is equipped with an air blowing pipe and an air suction pipe.

[0023] Furthermore, the workbench is provided with a discharge plate, the discharge plate is provided with a fourth track, and the third track is provided with a fourth sliding gripper.

[0024] Compared with existing technologies, the advantages of this invention lie in its application of five-axis laser engraving technology. By adjusting the parameters of different lasers, the surface of plastics is roughened and modified according to their properties, making it adaptable to various spherical and three-dimensional material products. Then, a conductive metal layer is deposited on the roughened surface using a catalyst solution. This conductive metal layer acts as a locking mechanism with the roughened material surface, allowing the deposited metal particles to gradually thicken during the subsequent chemical plating reaction, thus forming a good bond with the material surface and achieving selective metallization of the plastic surface. Furthermore, this application simplifies the loading and unloading process through a feeding device, achieving semi-automatic feeding of the plastic carrier, saving labor costs in manufacturing, and significantly reducing equipment costs. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the process of the present invention.

[0026] Figure 2 This is a 3D view of the external structure of a five-axis laser engraving device.

[0027] Figure 3 This is another three-dimensional view of the external structure of a five-axis laser engraving device.

[0028] Figure 4 This is a schematic diagram of the internal structure, which is a three-dimensional view of the external structure.

[0029] Figure 5 This is a cross-sectional structural diagram of a five-axis laser engraving device.

[0030] Figure 6 for Figure 4 A magnified view of a portion of region A in the middle.

[0031] Figure 7 for Figure 4 A magnified view of a portion of region B in the middle.

[0032] In the picture:

[0033] Frame 1, Automatic feeding device 2, Feed column 21, Feed inlet 211, Worktable 22, Internal gear ring 221, Annular guide groove 222, Lifting platform 23, Positioning groove 231

[0034] 232, rotating table 24, connecting part 241, guide arm 242, drive motor 25, feeding channel 26, turntable 27, rotating shaft 271, first gear 272, guide cylinder 273, positioning plate 28, inclined guide part 281, discharge plate 29, laser device 3, dust cover 4, air blowing pipe 41, air suction pipe 42, first track 51, first sliding gripper 52.

[0035] Second track 53, second sliding gripper 54, third track 55, third sliding gripper 56, fourth track 57, fourth sliding gripper 58, loading station 61, processing station 62.

[0036] Material feeding station 63, plastic carrier 71, roughening area 72, conductive material 73.

[0037] Metal layer 74. Detailed Implementation

[0038] To further explain the technical solution of the present invention, the present invention will be described in detail below through specific embodiments.

[0039] like Figure 1-7 As shown, a manufacturing process for 3D metal circuits includes the following steps:

[0040] S1. Design the structure of the plastic carrier 71 according to requirements;

[0041] S2. Design and open the molding die for the plastic carrier 71;

[0042] S3. The plastic carrier 71 is injection molded using plastic material;

[0043] S4. Develop and tailor laser parameters for different plastic materials;

[0044] S5. Applying five-axis laser engraving technology, by adjusting the parameters of different lasers, the surface of plastics is roughened and modified according to the properties of different plastics.

[0045] S6. A layer of conductive material 73 is deposited on the roughened area 72 of the surface of the plastic carrier 71 using a catalyst solution;

[0046] S7. Perform chemical electroplating on the surface of the plastic carrier 71 to form a metal layer 74.

[0047] This invention utilizes five-axis laser engraving technology. By adjusting the parameters of different lasers, the surface of plastics is roughened and modified according to their properties, making it adaptable to various spherical and three-dimensional material products. Then, a conductive material 73 is deposited onto the roughened area 72 using a catalyst solution. This conductive metal layer 74 acts as a locking mechanism with the roughened material surface, allowing the deposited metal particles to gradually thicken during subsequent chemical plating reactions and forming a strong bond with the material surface, thus achieving selective metallization of the plastic surface. The combination of catalyst solvent and laser surface roughening is a key technological innovation of this invention. It solves the problems of traditional processes requiring the addition of metal particles to plastics, limiting processing to LPKF-specified materials with extremely high costs, requiring dedicated LPKF machines with high equipment costs, and restricting the use of high-frequency (5G) technology. Furthermore, this invention uses five-axis laser engraving technology, fully utilizing all space on the product surface with penetrability, saving space, simplifying the process, and enabling miniaturization of the product. It has design advantages such as the ability to choose shapes and functions according to design needs, and to be suitable for the development trend of smaller and lighter products; it also has the advantages of reducing installation layers, reducing the number of components, and improving reliability, and will have a considerable number of applications in fields such as 5G base stations, automotive signal connection mechanisms, precision industrial equipment, medical products, calculators, and communications.

[0048] Preferably, the molding material of the plastic carrier 71 can be selected from one of the following materials: PET, LCP, PPS, or Bakelite. In this embodiment, the plastic carrier 71 is injection molded from PET material, and the surface of the plastic carrier 71 is roughened by laser engraving. The laser wavelength is 2000-1300nm, the laser frequency is 50-180kHz, the laser movement speed is 200-5000mm / s, the laser irradiation is performed more than twice, and the depth of the roughened surface area after laser irradiation is 3-10μm. After the surface of the plastic carrier 71 is modified, a tin activator is applied to the roughened area 72 for catalysis. The tin activator contains hydrochloric acid, stannous chloride, palladium chloride, potassium tetracyanopallate, and / or additives. More specifically, the tin activator is an acidic solution containing HCl (150-300ml / L), SnC (10-15g / L), and PdCl2 (0.5-1g / L). The tin activator is composed of palladium (Pd), tin ions (Sn2+), and chloride ions (Cl-), forming a palladium-tin chloride compound (such as Pd(SnCl3)) colloidal particles, which is stable in acidic solutions. When the substrate is immersed in the tin activator, the substrate first adsorbs tin ions (Sn2+) from the tin activator, and then adsorbs chloride ions (Cl-) from the solution, or utilizes the positive charge of the substrate surface to adsorb chloride ions (Cl-) from the solution; then an adsorption film layer is formed, followed by the adsorption of colloidal palladium particles generated during solution preparation. Under certain conditions, a redox reaction occurs, producing a conductive material layer 73. This is then followed by chemical electroplating, such as electroless copper plating, electroless nickel plating, electroless copper-nickel plating, etc. In this embodiment, electroless plating is used to deposit a copper layer on the substrate surface to form a circuit.

[0049] Preferably, in order to achieve automated feeding of the plastic carrier 71 during five-axis laser engraving, a five-axis laser engraving device is used in S5 to roughen and modify the plastic material. The five-axis laser engraving device includes a frame 1, an automatic feeding device 2, a laser device 3, and a dust cover 4. The automatic feeding device 2 includes a first track 51, a feeding column 21, a worktable 22, a lifting platform 23, a rotary table 24, and a drive motor 25. The feeding column 21 is mounted on the frame 1, and the side wall of the feeding column 21 is provided with a feed... The feed inlet 211 has a first track 51 located on its outer side, extending towards the feed inlet 211. A first sliding gripper 52 is mounted on the first track 51. An inclined guide plate is located at the end of the first track 51 furthest from the feed inlet 211. The plastic carrier 71 is conveyed to the end of the first track 51 via a conveyor belt. The inclined guide plate guides the plastic carrier 71, concentrating it at the end of the first track 51 for easy gripping by the first sliding gripper 52. The lower end of the rotary table 24 has a connecting part 241, which is rotatably connected to the feed column 21 via a bearing. The drive motor 25 drives the connecting part 241 to rotate, thus rotating the rotary table 24. Specifically, the drive motor 25 has a drive gear at its power output end, and a transmission gear is mounted on the connecting part 241. When the drive motor 25 is turned on, it drives the drive gear to rotate, thereby transmitting power through the transmission gear and rotating the rotating part and the rotary table 24.

[0050] The feeding column 21 and the rotary table 24 are provided with a feeding channel 26 in the middle. The lifting platform 23 is located in the feeding channel 26 and moves up and down. Specifically, the feeding channel 26 is provided with a lifting slide rail, and the lifting platform 23 is mounted on the lifting slide rail. The upper surface of the lifting platform 23 is provided with a positioning groove 231, and the two sides of the positioning groove 231 are provided with clearance grooves 232. The clearance grooves 232 can provide clearance for the first sliding gripper 52 and the second sliding gripper 54. The rotary table 24 is provided with guide arms 242 evenly arranged along the circumference of the rotary table 24. The end of the guide arm 242 is provided with a turntable 27 rotatably connected to it. The guide arm 242 is provided with a second track 53, and the second sliding gripper 54 is provided on the second track 53. The turntable 27 is provided with a third track 55, and the third sliding gripper 56 is provided on the third track 55. Each turntable 27 on the rotary table 24 represents a workstation. The main workstations on the rotary table 24 include a loading station 61, a processing station 62, and a unloading station 63. The second track 53 and the third track 55 on the loading station 61 are aligned with the positioning groove 231 on the lifting platform 23, facilitating the transport of the plastic carrier 71 to the turntable 27. The workbench 22 is fixedly connected to the frame 1. A through hole is provided in the middle of the workbench 22, through which the connecting part 241 can pass. The dust cover 4 is installed above the rotary table 24. The laser device 3 is installed on the dust cover 4. The dust cover 4 has a feed hole and a discharge hole on both sides. The processing station 62 is located inside the dust cover 4 to prevent dust and smoke generated during laser lithography from spreading outward, ensuring a clean working environment. The unloading station 63 is located outside the discharge hole. After the plastic carrier 71 on the turntable 27 is processed, it is driven to the unloading station 63 for automatic unloading. A transition station is provided between the loading station 61 and the unloading station 263, and a positioning plate 28 is also provided on the turntable 27. The positioning plate 28 is located above the third guide rail and is connected to the turntable 27 by a spring. The front end of the positioning plate 28 is provided with an inclined guide part 281. When the plastic carrier 71 enters the turntable 27, the positioning plate 28 can press the two sides of the plastic carrier 71, making the plastic carrier 71 more firmly fixed on the turntable 27. At the same time, the inclined guide part 281 can guide the plastic carrier 71 to enter the positioning plate 28 more smoothly.

[0051] More preferably, the lower end of the turntable 27 is provided with a rotating shaft 271, which is rotatably connected to the guide arm 242 via a bearing. A first gear 272 is provided on the rotating shaft 271, and an internal gear ring 221 is provided on the worktable 22. The first gear 272 meshes with the internal gear ring 221. When the turntable 24 rotates to change workstations, it drives each guide arm 242 to rotate around the axis of the feed column 21. During the rotation of the turntable 24, the first gear 272 and the internal gear ring 221 mesh and transmit power, causing the turntable 27 to rotate around the axis of the rotating shaft 271. Furthermore, the number of teeth between adjacent workstations is an integer multiple of the number of teeth on the first gear 272, ensuring that the plastic carrier 71 maintains a consistent orientation during workstation changes. The worktable 22 is provided with an annular guide groove 222, and the lower end of the rotating shaft 271 is provided with a guide cylinder 273 that is slidably connected within the annular guide groove 222. When the rotary table 24 rotates, the guide cylinder 273 cooperates with the annular guide groove 222 to guide the rotation, while lowering the center of gravity of the rotary table 24, making the rotation of the rotary table 24 more stable. Before the plastic carrier 71 enters the processing station 62, the turntable 27 drives the plastic carrier 71 to rotate, causing gas flow around the plastic carrier 71, which facilitates the blowing off of dust on the surface of the plastic carrier 71, improving the processing quality of the product. After the plastic carrier 71 is laser-processed, the turntable 27 can also drive the plastic carrier 71 to rotate, clearing the dust generated in the roughened area 72 of the plastic carrier 71, making the surface of the plastic carrier 71 cleaner. At the same time, the rotation process also has a cooling effect, accelerating the cooling rate of the surface of the roughened area 72, which facilitates catalytic solvent treatment, improving processing efficiency and activation quality.

[0052] More preferably, the dust cover 4 is equipped with an air blowing pipe 41 and an air suction pipe 42. The air blowing pipe 41 can blow air onto the processed plastic carrier 71, making the roughened area 72 on the surface of the plastic carrier 71 cleaner, facilitating catalytic solvent treatment and improving catalytic quality. The air suction pipe 42 can absorb the smoke and dust generated during processing inside the dust cover 4, further preventing the spread of dust and smoke. Furthermore, the workbench 22 is equipped with a discharge plate 29, which is located on the side of the unloading station 63. The discharge plate 29 is equipped with a fourth track 57, and the fourth track 57 is equipped with a fourth sliding gripper 58. When the plastic carrier 71 moves to the unloading station 63, the fourth sliding gripper 58 clamps the plastic carrier 71 on the turntable 27 and places it in the storage area for storage.

[0053] The specific workflow of the five-axis laser engraving equipment is as follows: During operation, the lifting platform 23 moves to the lowest point of the feeding channel, level with the first track 51. The plastic carrier 71 is conveyed to the side of the first track 51 via a conveyor belt or manually. The first sliding gripper 52 grips the lower part of the plastic carrier 71, moves the plastic carrier 71 onto the lifting platform 23, and pushes it into the positioning groove 231 for fixation. Then, the lifting platform 23 rises to the rotary table 24. The gripper on the second track 53 moves to the clearance groove 232 to grip the lower part of the plastic carrier 71 and moves it towards the turntable 27. When the plastic carrier 71 moves to the side of the turntable 27, the gripper on the third track 55 grips the middle part of the plastic carrier 71 and moves it onto the turntable 27 for fixation. Afterward, the drive motor 25 drives the rotary table 24 to rotate. During the rotation of the rotary table 24, the first gear 272 meshes with the internal gear ring 221, causing the turntable 27 and the plastic carrier 71 to rotate. After the plastic carrier 71 enters the processing station 62, the five-axis laser device 3 performs 3D laser processing on the surface of the plastic carrier 71. Then, the turntable 27 moves to the unloading station 63, and the fourth sliding gripper 58 clamps the plastic carrier 71 on the turntable 27 and places it in the storage area for storage. In this process, laser positioning devices are installed on the first track 51, the second track 53, the third track 55, and the fourth track 57 to ensure that each sliding gripper can clamp the plastic carrier 71 to the designated position. The sliding grippers can be pneumatic grippers. The above-mentioned sliding gripper structure is a conventional setting method for those skilled in the art, so it will not be described in detail.

[0054] The five-axis laser engraving equipment enables automated feeding of the plastic carrier 71 in this process. It features a reasonable structure, simple operation, and significantly reduces manual labor. Before the plastic carrier 71 enters the processing station 62, the turntable 27 rotates it, causing airflow around the carrier. This facilitates the removal of dust from the surface of the carrier, improving product processing quality. After laser engraving, the turntable 27 continues to rotate the carrier, clearing dust from the roughened area 72 and resulting in a cleaner surface. The rotation also provides a cooling effect, accelerating the cooling of the roughened area 72, which is beneficial for catalytic solvent treatment, thus improving processing efficiency and activation quality.

[0055] The above embodiments and figures are not intended to limit the product form and style of the present invention. Any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of the present invention.

Claims

1. A manufacturing process for 3D metal circuits, characterized in that, Includes the following steps: S1. Design the plastic carrier structure according to requirements; S2. Design and develop molding dies for plastic carriers; S3. The plastic carrier is injection molded using plastic material; S4. Develop and tailor laser parameters for different plastic materials; S5. Applying five-axis laser engraving technology, by adjusting the parameters of different lasers, the surface of plastics is roughened and modified according to the properties of different plastics. S6. A conductive material is deposited on the roughened area of ​​the plastic carrier surface using a catalyst solution; S7. Perform chemical electroplating on the surface of the plastic carrier to form a metal layer; The S5 uses a five-axis laser engraving device to roughen and modify plastic materials. This device includes a frame, an automatic feeding device, a laser engraving unit, and a dust cover. The automatic feeding device includes a first track, a feeding column, a worktable, a lifting platform, a rotary table, and a drive motor. The feeding column is mounted on the frame, and its side wall has a feeding port. The first track is located outside the feeding port and has a first sliding gripper. The lower end of the rotary table has a connecting part that is rotatably connected to the feeding column. The drive motor drives the connecting part to rotate. The rotating table is driven to rotate. The feeding column and the middle of the rotating table are provided with a feeding channel. The lifting platform is located in the feeding channel and moves up and down. The rotating table is provided with guide arms that are evenly arranged along the circumference of the rotating table. The end of the guide arm is provided with a turntable that is rotatably connected. The guide arm is provided with a second track and a second sliding gripper. The turntable is provided with a third track and a third sliding gripper. The worktable is fixedly connected to the frame. The middle of the worktable is provided with a through hole. The dust cover is located above the rotating table. The laser device is installed on the dust cover.

2. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The molding material of the plastic carrier includes PET, LCP, PPS or bakelite.

3. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The thickness of the metal layer is ≥18μm.

4. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The catalyst solution may be made of tin activator.

5. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The lower end of the turntable is provided with a rotating shaft, which is rotatably connected to the guide arm. A first gear is provided on the rotating shaft, and an internal gear ring is provided on the worktable. The first gear is meshed with the internal gear ring.

6. The manufacturing process of a 3D metal circuit as described in claim 5, characterized in that, The worktable is provided with an annular guide groove, and the lower end of the rotating shaft is provided with a guide cylinder that is slidably connected and embedded in the annular guide groove.

7. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The feeding channel is equipped with a lifting slide rail, and the lifting platform is installed on the lifting slide rail. The upper surface of the lifting platform is provided with a positioning groove, and the two sides of the positioning groove are provided with clearance grooves.

8. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The dust cover is equipped with an air blowing pipe and an air suction pipe.

9. The manufacturing process of a 3D metal circuit as described in claim 1, characterized in that, The workbench is provided with a discharge plate, the discharge plate is provided with a fourth track, and the third track is provided with a fourth sliding gripper.

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