A method for laser cutting of microwave high-frequency dielectric substrate patterns

Abstract

This application discloses a laser cutting method for patterns on a microwave high-frequency dielectric substrate, comprising: pre-treatment of the microwave high-frequency dielectric substrate using acid pickling and back-side film application; placing the microwave high-frequency dielectric substrate on a vacuum adsorption stage and fixing the substrate in place by turning on the vacuum; acquiring laser forming files, laser parameters, and positioning points; positioning the microwave high-frequency dielectric substrate using the positioning points; performing laser cutting on the microwave high-frequency dielectric substrate using the laser forming files and laser parameters; peeling off the back-side film from the cut microwave high-frequency dielectric substrate and treating the surface by immersion in anhydrous ethanol. The above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns disclosed in this application can improve cutting accuracy, increase yield, and reduce production costs.

Description

Technical Field

[0001] This invention belongs to the field of microwave equipment manufacturing technology, and in particular relates to a laser cutting method for microwave high-frequency dielectric substrate patterns. Background Technology

[0002] The printed circuit board (PCB) cutting and forming process is a major step in PCB manufacturing. Its purpose is to cut the PCB's internal grooves and external shape according to pre-designed dimensions, producing products that meet assembly requirements. Current mass production methods for PCB cutting primarily utilize CNC milling machine mechanical forming processes, including the following steps: PCB fabrication, incoming material inspection, PCB film application, substrate marking, cutting document editing, cross-checking and confirmation of cutting documents, milling machine positioning, drilling positioning holes and attaching pins to the machine table, PCB loading, application of phenolic resin cover plate and securing with masking tape, process parameter calling and confirmation, cutting commencement, unloading and film removal, graphic inspection, screening, and packaging for shipment. Printed circuit board (PCB) molding typically employs a 4-axis CNC milling machine paired with specialized high-speed tungsten carbide cutters, meeting the molding requirements of conventional PCBs. Specifically, the milling process involves several steps: first, pre-treatment of the PCB surface is performed, applying a moderately viscous white film to both sides to protect the pattern. Then, a pin-punching machine is used to drill pin holes at the locating holes on the PCB for subsequent pin installation. Next, the molding file is edited, including the cutting position, molding trajectory, and breakpoint connection points. After the file is edited, the PCB is loaded, the pin holes are drilled, a phenolic cover plate is applied, and the PCB is secured with adhesive tape. Finally, molding is performed according to the product's process parameters. This molding step is critical, requiring settings for the milling cutter's speed, feed rate, depth of cut, and number of cuts. After molding, the PCB is inspected. This existing molding method offers high efficiency, with a cutting feed rate typically between 1 and 2 m / min, suitable for mass-produced consumer products. Furthermore, the mechanical molding accuracy is generally ±50 μm, basically meeting the quality requirements of ordinary FR4 consumer PCBs. However, this existing mechanical forming and cutting process has two problems, which make it unable to meet the high requirements of military microwave high-frequency dielectric substrates. The main problems include: First, the forming accuracy is not high, generally ±50um, and "ear" arcs are easily generated at the cutting position, affecting the appearance quality. With the widespread application of military microwave and millimeter-wave products, the quality requirements of microwave high-frequency dielectric substrates, which play a key role in information transmission, are also getting higher and higher. The accuracy and shape of the "wave pinhole" at the device mounting position, the signal transmission line must be in the center position, etc., constantly test the level of substrate processing technology.As customer product quality requirements continue to rise, the ±50µm accuracy of conventional mechanical forming is no longer sufficient. ±50µm is already the limit of CNC milling machine accuracy, and no further adjustments can be made. Furthermore, the spindle of mechanical forming, due to its continuous rise and fall along the Z-axis during operation, is prone to oscillation at the cutting position, creating "ear"-like arcs, causing quality abnormalities and affecting subsequent assembly processes. Secondly, burrs are easily generated along the cutting path of mechanical forming, requiring significant manpower and time for manual removal. Some internal grooves are extremely difficult to remove burrs, resulting in substandard appearance quality. This is a common problem in the microwave high-frequency dielectric substrate cutting and forming industry, and remains unresolved. Specialized personnel are needed to manually remove burrs with scalpels, or plasma deburring processes can be used, but complete burr removal cannot be guaranteed. Therefore, for products with high appearance quality requirements, only product screening and delivery are possible, leading to lower yield and increased production costs. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a laser cutting method for microwave high-frequency dielectric substrate patterns, which can improve cutting accuracy, increase yield, and reduce production costs.

[0004] The present invention provides a laser cutting method for patterns on microwave high-frequency dielectric substrates, comprising:

[0005] Pretreatment and back-side lamination of microwave high-frequency dielectric substrates are performed using acid pickling.

[0006] The microwave high-frequency dielectric substrate is placed on a vacuum adsorption stage, and the vacuum is turned on to fix the microwave high-frequency dielectric substrate.

[0007] Obtain laser forming files, laser parameters, and positioning points;

[0008] The microwave high-frequency dielectric substrate is positioned using the positioning points, and the microwave high-frequency dielectric substrate is laser-cut using the laser forming file and the laser parameters.

[0009] The film on the back of the cut microwave high-frequency dielectric substrate is peeled off, and the surface is treated by immersion in anhydrous ethanol.

[0010] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, after the surface treatment by immersion in anhydrous ethanol, the method further includes:

[0011] The color difference on the surface of the microwave high-frequency dielectric substrate is removed by using weak acid micro-etching, sandblasting, and ultrasonic pure water cleaning.

[0012] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, the pretreatment of the microwave high-frequency dielectric substrate using acid pickling includes:

[0013] The microwave high-frequency dielectric substrate is immersed in oxalic acid for 25 to 35 minutes, and then in hydrochloric acid for 20 to 25 minutes.

[0014] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, the back-side lamination of the microwave high-frequency dielectric substrate is as follows:

[0015] A soft adhesive film is attached to the back of a microwave high-frequency dielectric substrate.

[0016] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, the vacuum adsorption stage has 25 to 30 square perforated areas with a width of 100 mm to 105 mm, and each perforated area is provided with 45 to 55 vacuum adsorption holes with a diameter of 1.8 mm to 2.2 mm.

[0017] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, the thickness of the vacuum adsorption stage is 10 mm to 12 mm.

[0018] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, when the thickness of the microwave high-frequency dielectric substrate is 0.127 mm and there are no process lines, the laser parameters are as follows: cutting speed is 400 mm / s to 450 mm / s, power is 13.5 W to 14.0 W, galvanometer scan count is 40 to 45, and focal length offset is 0 μm.

[0019] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, when the thickness of the microwave high-frequency dielectric substrate is 0.127 mm and it has process lines and inner groove cross-sections for gold cutting, the laser parameters are divided into two cutting stages: the first cutting speed is 400 mm / s to 450 mm / s, the power is 13.5 W to 14.0 W, the number of galvanometer scans is 40 to 45, and the focal length shift is 0 μm; the second cutting speed is 700 mm / s to 800 mm / s, the power is 14.5 W to 15.0 W, the number of galvanometer scans is 25 to 30, and the focal length shift is 120 μm.

[0020] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, when the thickness of the microwave high-frequency dielectric substrate is 0.254 mm and there are no process lines, the laser parameters are as follows for one-time cutting: cutting speed of 400 mm / s to 450 mm / s, power of 15.2 W to 15.8 W, galvanometer scanning times of 40 to 45, and focal length offset of 0 μm.

[0021] Preferably, in the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, when the thickness of the microwave high-frequency dielectric substrate is 0.254 mm and it has process lines and inner groove cross-sections for gold cutting, the laser parameters are divided into two cutting stages: the first cutting speed is 400 mm / s to 450 mm / s, the power is 15.2 W to 15.8 W, the number of galvanometer scans is 55 to 60, and the focal length shift is 0 μm; the second cutting speed is 700 mm / s to 800 mm / s, the power is 15.5 W to 16.2 W, the number of galvanometer scans is 25 to 30, and the focal length shift is 120 μm.

[0022] As described above, the laser cutting method for the microwave high-frequency dielectric substrate pattern provided by the present invention includes: pre-treatment of the microwave high-frequency dielectric substrate and back-side film application using acid pickling; placing the microwave high-frequency dielectric substrate on a vacuum adsorption stage and fixing the microwave high-frequency dielectric substrate by turning on the vacuum; obtaining laser forming files, laser parameters, and positioning points; positioning the microwave high-frequency dielectric substrate using the positioning points; performing laser cutting on the microwave high-frequency dielectric substrate using the laser forming files and the laser parameters; peeling off the back-side film of the cut microwave high-frequency dielectric substrate; and treating the surface by immersion in anhydrous ethanol. It is evident that by adopting this laser cutting method, cutting accuracy can be improved, yield can be increased, and production costs can be reduced. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of an embodiment of a laser cutting method for a microwave high-frequency dielectric substrate pattern provided by the present invention;

[0025] Figure 2 This is a schematic diagram of a vacuum adsorption stage provided in this application. Detailed Implementation

[0026] The core of this invention is to provide a laser cutting method for microwave high-frequency dielectric substrate patterns, which can improve cutting accuracy, increase yield, and reduce production costs.

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] An embodiment of the laser cutting method for microwave high-frequency dielectric substrate patterns provided by the present invention is as follows: Figure 1 As shown, Figure 1 This is a schematic diagram of an embodiment of a laser cutting method for a microwave high-frequency dielectric substrate pattern provided by the present invention. The method may include the following steps:

[0029] S1: Pretreatment and back-side film application of microwave high-frequency dielectric substrate using acid pickling method;

[0030] It should be noted that this pickling method not only does not affect the substrate itself, but also has a good effect on removing copper layer oxidation and substrate surface discoloration. It is easy to operate and is more suitable for laser target positioning after such treatment.

[0031] S2: Place the microwave high-frequency dielectric substrate on the vacuum adsorption stage and turn on the vacuum to fix the microwave high-frequency dielectric substrate.

[0032] It should be noted that this vacuum adsorption stage can firmly fix the microwave high-frequency dielectric substrate, ensuring that it will not shift during the laser cutting process, thereby ensuring higher precision in laser cutting.

[0033] S3: Obtain laser forming files, laser parameters, and positioning points;

[0034] Specifically, when editing laser forming files, firstly, the target and forming trajectory must not have repeating line segments. The laser forming trajectory runs exactly according to the trajectory lines in the CAD drawing. If there are repeating line segments, the system will default to multiple processing. Selecting any positioning target and copying the internal and external milling files by the base point results in no problems merging the internal and external milling files, and no duplicate or redundant trajectories appear. However, after the target point is copied, the trajectory is multiplied by 2, causing the target positioning software to fail to recognize it and report an error. Similarly, if the forming file has repeating trajectories, the number of laser processing scans will also be multiplied accordingly, increasing the possibility of thermal effects. Therefore, redundant repeating line segments on the target and forming trajectory must be deleted. Secondly, when editing laser forming files using CAM350... After conversion, the tool deflection distance cannot be set; secondly, select a 1.5mm target for alignment, with a clear and bright surface. The number of breakpoints should not be too many, with no more than one on each edge. Set the breakpoint spacing to 0.5mm to avoid difficulties in cutting for the user. Specifically, identify the photolithography circuit diagram and the forming path diagram. Delete the photolithography circuit diagram, keeping the forming path diagram. Delete any redundant positioning holes around the forming path diagram, keeping only two positioning circles on each side. If the graphic expands or contracts excessively, additional positioning circles can be added in the middle of the graphic. At this time, check whether the positioning circle arcs are smooth and have a center. Then, set the graphic breakpoints according to the process requirements. Enter the "br" command in the command box, then left-click the line where a breakpoint needs to be made and enter the breakpoint. Set the size to 0.5mm, then press "Enter". The breakpoint must be placed within a straight line area to ensure ease of subsequent removal. After setting all breakpoints, save the file as a *.dxf2004 file. Then confirm the laser software parameters. If the laser control parameters are restarted after powering off, a remote control command must be entered. After turning on the laser, use a power meter to measure the actual laser power, which must meet the process technical standards. Next, edit the positioning points. After setting the laser parameters and completing the CAD forming file as required, it needs to be imported into the graphics software for target selection and cutting file format conversion. First, import the forming file in .dxf format, then select a copper disk with a diameter of 1.5mm. To locate the target as a whole, the corresponding cutting file is output to complete this process. The laser forming cutting trajectory should ideally not overlap with the dotted line of the galvanometer to avoid affecting the forming quality. Finally, process parameters are confirmed and processed: Step 1 is to input the total material thickness of the aluminum alloy perforated pad and the substrate to be formed. The substrate is measured with calipers before forming. Generally, for a 0.127mm substrate, the material thickness is set to 1830mm; for a 0.254mm substrate, the material thickness is set to 1950mm. After setting, CCD focusing is performed to ensure image clarity; otherwise, the Z value is adjusted. Step 2 is substrate loading. It is important to ensure that all vacuum adsorption holes except for the substrate are covered with cardboard to ensure a vacuum adsorption strength <= -20.0. After vacuum adsorption, it can be moved slightly by hand; generally, no additional adhesive tape is needed. Step 3 is disk positioning. Slowly move the CCD lens to the first positioning target in the lower left corner, then identify and grasp all targets one by one, and perform a target grasping test. The identification accuracy error must be controlled within ±0.005um. Step 4 is setting the cutting process parameters. The suitable thicknesses for microwave high-frequency dielectric substrates for laser cutting are mainly 0.127mm and 0.254mm, which are further divided into products with and without process lines.

[0035] S4: Position the microwave high-frequency dielectric substrate using positioning points, and perform laser cutting on the microwave high-frequency dielectric substrate using laser forming files and laser parameters.

[0036] This step can be performed using, but is not limited to, a 30W ultraviolet picosecond laser processing device for laser cutting.

[0037] S5: Peel the film off the back of the cut microwave high-frequency dielectric substrate and treat the surface by immersion in anhydrous ethanol.

[0038] The following is a specific example to illustrate this step: After the substrate is processed, the back film is peeled off. At this time, the cut edge of the substrate may discolor and turn black due to the thermal effect. This is because when the picosecond laser acts on the substrate surface for cutting, although the scanning speed is higher than 400mm / s under the action of the galvanometer, the instantaneous temperature of the laser beam is still higher than 600℃. The microwave high-frequency dielectric substrate is double-sided copper-clad, and the middle is generally a dielectric board made of polytetrafluoroethylene. Under high temperature, the dielectric material will carbonize and turn black. Once the discoloration and blackening of the material are found after laser cutting, the following measures should be taken: Use a lint-free cloth dipped in 99% anhydrous ethanol solution to gently wipe the front, back and sides of the substrate. Do not wipe with too much force to scratch the substrate surface. After treatment with anhydrous ethanol solution, the blackening of the substrate can be basically resolved.

[0039] As described above, the embodiment of the laser cutting method for microwave high-frequency dielectric substrate patterns provided by the present invention includes: pre-treatment and back-side film application of the microwave high-frequency dielectric substrate using acid pickling; placing the microwave high-frequency dielectric substrate on a vacuum adsorption stage and fixing it in place by turning on the vacuum; obtaining laser forming files, laser parameters, and positioning points; positioning the microwave high-frequency dielectric substrate using the positioning points; laser cutting the microwave high-frequency dielectric substrate using the laser forming files and laser parameters; peeling off the back-side film of the cut microwave high-frequency dielectric substrate; and surface treatment by immersion in anhydrous ethanol. It is evident that this laser cutting method can improve cutting accuracy, increase yield, and reduce production costs.

[0040] In a specific embodiment of the laser cutting method for the above-mentioned microwave high-frequency dielectric substrate pattern, after surface treatment with anhydrous ethanol immersion, the following steps may be included: removing color differences on the surface of the microwave high-frequency dielectric substrate using weak acid micro-etching, sandblasting, and ultrasonic pure water cleaning. The following is a detailed explanation of this step using a specific example: The substrate, after being wiped with anhydrous ethanol, is then sandblasted. Sandblasting primarily eliminates color differences caused by the alcohol's effect on the substrate surface and also helps to remove some thermal effects, resulting in better surface quality. The sandblasting speed can be selected as 800-1200 mm / min. The substrate first passes through a weak acid micro-etching section, then a sandblasting section, and finally an ultrasonic pure water cleaning section. After drying, the thermal effects on the substrate surface are completely resolved.

[0041] In another specific embodiment of the laser cutting method for the above-mentioned microwave high-frequency dielectric substrate pattern, the pretreatment of the microwave high-frequency dielectric substrate by acid pickling may include the following steps:

[0042] The microwave high-frequency dielectric substrate is immersed in oxalic acid for 25 to 35 minutes, and then in hydrochloric acid for 20 to 25 minutes. A specific example is provided below to illustrate this embodiment: For military-grade microwave high-frequency dielectric substrates, due to the requirements of subsequent gold wire bonding assembly, the surface is generally electroplated with a thin layer of gold of about 2µm, while the underlying copper metal thickness is generally above 35µm. After a period of time, various contaminants and discoloration appear on the substrate surface. Before laser forming, the contaminants on the substrate surface will affect the CCD's recognition of the positioning holes, causing deviations in laser forming accuracy. Therefore, before laser forming, it is immersed in oxalic acid for 30 minutes, and then in hydrochloric acid for 20 minutes, because the microwave high-frequency dielectric substrate... The surface treatment uses immersion gold or electroplating thin gold processes, with a gold layer thickness generally below 2µm. During processing, due to the thin gold layer, the underlying copper metal easily migrates to the surface, causing surface discoloration. Furthermore, due to cost considerations, gold plating is typically only applied to the patterned areas; the non-patterned and target areas remain copper. Copper is a metal that oxidizes very easily when exposed to air, and without treatment, it easily discolors, turning yellow or red. While this has no effect on ordinary mechanical forming of target holes, laser forming uses machines to automatically identify target hole positions. If the target pattern is not clearly visible, it cannot be identified. This pickling solution uses oxalic acid and hydrochloric acid for immersion treatment, which not only does not affect the substrate itself but also has a strong effect on removing copper layer oxidation and substrate surface discoloration. The operation is also very convenient; after cleaning, the next process can proceed.

[0043] In another specific embodiment of the laser cutting method for the above-mentioned microwave high-frequency dielectric substrate pattern, the back-side film application to the microwave high-frequency dielectric substrate can be achieved by applying a soft adhesive film to the back side of the substrate. The soft adhesive film has a certain viscosity and flexibility, ensuring that the film can adhere tightly to the back side of the substrate. A specific example is given below to illustrate this embodiment: When applying the film, only the back side needs protection. Because the heat generated during laser processing interacts with the back side of the substrate, it will cause a severe thermal effect. Applying the film to the back side for protection and then peeling it off after laser forming results in a lower thermal effect. It can be largely removed after sandblasting. A soft adhesive blue film with the following parameters can be used: viscosity of 12N / 25mm and elastic modulus of 1.5GPa. This not only provides protection but also makes removal relatively easy.

[0044] In a preferred embodiment of the laser cutting method for the above-mentioned microwave high-frequency dielectric substrate pattern, the vacuum adsorption stage has 25 to 30 square perforated areas with a width of 100 mm to 105 mm, and each perforated area has 45 to 55 vacuum adsorption holes with a diameter of 1.8 mm to 2.2 mm. Further, the thickness of the vacuum adsorption stage is preferably 10 mm to 12 mm. A specific example is given below to illustrate this embodiment: Figure 2 As shown, Figure 2 This is a schematic diagram of a vacuum adsorption stage provided in this application. During the cutting process of the substrate, the smoother the surface and the closer the contact with the bottom support plate, the better the processing effect. Therefore, this perforated vacuum adsorption stage is used to achieve the vacuum adsorption effect through an external vacuum machine. The material of the vacuum adsorption stage can preferably be 304 stainless steel. The design has a square perforated area with a width of 105mm, with a total of 5*6 perforated areas. Each area is designed with 49 vacuum adsorption holes with a diameter of 2.0mm. The thickness of the vacuum adsorption stage is preferably 12mm. The thickness, hole diameter, and array hole position design of this vacuum adsorption stage can ensure both strength and durability during laser processing. The hole diameter can effectively adsorb and collect material debris after laser cutting of the substrate into the dust collection bin while ensuring the vacuum adsorption effect. If the hole diameter is too large, it will cause the substrate to collapse at the vacuum adsorption hole position, resulting in poor processing accuracy. If the hole diameter is too small, the debris after laser cutting will block the hole position, resulting in poor vacuum adsorption effect. The substrate is very easy to shift during the cutting process, and the processing accuracy of the substrate cannot be guaranteed. This vacuum adsorption stage has undergone long-term product verification and can meet the processing requirements of substrates of various sizes. The 304 stainless steel material can not only ensure the adsorption of substrates, but also dissipate the heat generated during laser processing and collect processing debris, which can effectively reduce the blackening phenomenon on the substrate surface after laser processing.

[0045] Based on the various embodiments of the above-mentioned laser cutting method for microwave high-frequency dielectric substrate patterns, when the thickness of the microwave high-frequency dielectric substrate is 0.127 mm and there are no process lines, the laser parameters are as follows for one-time cutting: cutting speed is 400 mm / s to 450 mm / s, power is 13.5 W to 14.0 W, galvanometer scanning times are 40 to 45, and focal length offset is 0 μm.

[0046] Furthermore, when the thickness of the microwave high-frequency dielectric substrate is 0.127 mm and it has process lines and inner grooves for gold cutting, the laser parameters are divided into two cutting stages: the first cutting speed is 400 mm / s to 450 mm / s, the power is 13.5 W to 14.0 W, the number of galvanometer scans is 40 to 45, and the focal length shift is 0 μm; the second cutting speed is 700 mm / s to 800 mm / s, the power is 14.5 W to 15.0 W, the number of galvanometer scans is 25 to 30, and the focal length shift is 120 μm. It should be noted that the purpose of the second laser cutting is to trim the process lines.

[0047] In another case, when the thickness of the microwave high-frequency dielectric substrate is 0.254 mm and there are no process lines, the laser parameters are as follows for one-time cutting: cutting speed of 400 mm / s to 450 mm / s, power of 15.2 W to 15.8 W, number of galvanometer scans of 40 to 45, and focal length offset of 0 μm.

[0048] In another scenario, when the thickness of the microwave high-frequency dielectric substrate is 0.254 mm and it has process lines and inner grooves for gold cutting, the laser parameters are divided into two cutting stages: the first cutting speed is 400 mm / s to 450 mm / s, the power is 15.2 W to 15.8 W, the number of galvanometer scans is 55 to 60, and the focal length shift is 0 μm; the second cutting speed is 700 mm / s to 800 mm / s, the power is 15.5 W to 16.2 W, the number of galvanometer scans is 25 to 30, and the focal length shift is 120 μm. It should be noted that the purpose of the second laser cutting is to trim the process lines.

[0049] It should also be noted that the above process parameters are the key to microwave high-frequency dielectric substrate laser cutting. In each product cutting process, a first article verification must be performed. The test part of the product is selected for cutting verification. Only when the effect of the first article meets the quality requirements of the laser processing process can formal mass production begin.

[0050] In summary, the laser cutting method for microwave high-frequency dielectric substrate patterns described above allows for direct editing of the cutting trajectory using CAD software. A special breakpoint connection method ensures that the substrate body and frame remain connected as a whole after cutting. Subsequent operations only require light cutting at the breakpoints, facilitating product application and transfer in later processes. When reviewing and editing laser forming files, it is crucial to check and handle duplicate line segments. This method ensures that the number of laser scans and the applied force meet process requirements, preventing overlapping effects. The resulting product exhibits less thermal effect and superior surface quality. Furthermore, the laser processing parameters employed achieve optimal laser cutting of the substrate, minimizing the number of laser scans and thermal effect while ensuring the microwave substrate can be cut through. This not only improves processing efficiency but also guarantees product quality after cutting. Additionally, surface thermal effects are eliminated after substrate cutting. Since high-frequency dielectric materials inherently exhibit "carbonization" during laser cutting, this solution uses a lint-free cloth soaked in 99%... Gently wipe the substrate (front, back, and sides) with a % anhydrous ethanol solution, provided that optimal cutting process conditions are used. If the blackening is too severe (exceeding 60% blackness or blackened edges exceeding 0.1mm), there is a 50% chance that anhydrous ethanol will not remove it. Treatment must be performed within 5 minutes of cutting. At this time, the substrate's thermal effect areas, due to residual heat from laser cutting (generally around 40℃), are more easily cleaned by anhydrous ethanol. If treatment is performed while the substrate is cooling, the effect will be significantly reduced, and the substrate surface treated with anhydrous ethanol is prone to developing mottled marks that are difficult to remove. In such cases, micro-etching and sandblasting with a weak acid solution can essentially remove the marks completely. It is important to note the thermal effect of laser cutting; key points are as follows: First, ensure the cutting process conditions are suitable to prevent excessive blackening; second, treat immediately after cutting to prevent carbonization and subsequent cooling that makes removal difficult; finally, address surface mottled marks caused by wiping and soaking with anhydrous ethanol, which can be cleaned with micro-etching and sandblasting with a weak acid solution.

[0051] The aforementioned laser cutting method for microwave high-frequency dielectric substrate patterns improves the processing accuracy of microwave high-frequency dielectric substrates, making it particularly suitable for products with high precision requirements. In the industry, the precision of ordinary mechanically formed products can only reach ±50µm tolerance. When forming special products with tight layouts, it is particularly easy to cut to the edge of the pattern or cause deviations within the holes. Laser forming, however, can achieve a precision of ±30µm, resulting in higher pattern cutting accuracy and better meeting the requirements of subsequent assembly processes. A common and unavoidable problem in the industry after mechanical cutting of microwave high-frequency materials is the formation of various burrs or rough edges on the pattern edges, especially in inner grooves or holes. These are difficult to remove manually and can severely affect subsequent assembly results and microwave parameters. Burrs or rough edges are the root cause of the problems in mechanical cutting processes. The laser cutting method provided in this application effectively solves the problem of burrs or rough edges. The substrate has excellent surface quality after cutting, with no burrs or rough edges, which is beneficial for subsequent assembly processes and results in better microwave parameter adjustment. Due to the high-speed rotation and frequent up-and-down movement of the mechanical forming spindle in the Z-axis direction, it is very easy to cause "ear" abnormalities on the substrate during the cutting process. The mounting holes or wave pin holes with high requirements for the internal groove assembly process cannot meet the assembly process requirements. Laser cutting forming with a processing accuracy of ±30um and the principle of direct spot action will not produce other abnormal shapes during the processing, resulting in better product processing effect.

[0052] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser cutting method for patterns on microwave high-frequency dielectric substrates, characterized in that, include: Pretreatment and back-side lamination of microwave high-frequency dielectric substrates are performed using acid pickling. The microwave high-frequency dielectric substrate is placed on a vacuum adsorption stage, and the vacuum is turned on to fix the microwave high-frequency dielectric substrate. Obtain laser forming files, laser parameters, and positioning points; The microwave high-frequency dielectric substrate is positioned using the positioning points, and then laser-cut using a 30W ultraviolet picosecond laser processing device based on the laser forming file and the laser parameters. The film on the back of the cut microwave high-frequency dielectric substrate is peeled off, and the surface is treated by immersion in anhydrous ethanol. After surface treatment by immersion in anhydrous ethanol, the method further includes: The color difference on the surface of the microwave high-frequency dielectric substrate is removed by using weak acid micro-etching, sandblasting and ultrasonic pure water cleaning. The pretreatment of the microwave high-frequency dielectric substrate using acid washing includes: The microwave high-frequency dielectric substrate is immersed in oxalic acid for 25 to 35 minutes, and then in hydrochloric acid for 20 to 25 minutes. The back-side lamination of the microwave high-frequency dielectric substrate is as follows: A soft adhesive film is attached to the back of a microwave high-frequency dielectric substrate; The vacuum adsorption stage has 25 to 30 square perforated areas with a width of 100 mm to 105 mm, and each perforated area is provided with 45 to 55 vacuum adsorption holes with a diameter of 1.8 mm to 2.2 mm.

2. The laser cutting method for microwave high-frequency dielectric substrate patterns according to claim 1, characterized in that, The thickness of the vacuum adsorption stage is 10 mm to 12 mm.

3. The method of laser cutting of microwave high frequency dielectric substrate patterns according to any one of claims 1-2, characterized in that, When the thickness of the microwave high-frequency dielectric substrate is 0.127 mm and there are no process lines, the laser parameters are as follows: for a single cut, the cutting speed is 400 mm / s to 450 mm / s, the power is 13.5 W to 14.0 W, the number of galvanometer scans is 40 to 45, and the focal length shift is 0 μm.

4. The method of laser cutting of microwave high-frequency dielectric substrate patterns according to any one of claims 1 to 2, characterized in that, When the thickness of the microwave high-frequency dielectric substrate is 0.127 mm and it has process lines and inner groove cross-sections for gold cutting, the laser parameters are divided into two cutting stages: the first cutting speed is 400 mm / s to 450 mm / s, the power is 13.5 W to 14.0 W, the number of galvanometer scans is 40 to 45, and the focal length shift is 0 μm; the second cutting speed is 700 mm / s to 800 mm / s, the power is 14.5 W to 15.0 W, the number of galvanometer scans is 25 to 30, and the focal length shift is 120 μm.

5. The laser cutting method for microwave high-frequency dielectric substrate patterns according to any one of claims 1-2, characterized in that, When the thickness of the microwave high-frequency dielectric substrate is 0.254 mm and there are no process lines, the laser parameters are as follows: cutting speed is 400 mm / s to 450 mm / s, power is 15.2 W to 15.8 W, galvanometer scan count is 40 to 45, and focal length offset is 0 μm.

6. The method of laser cutting of microwave high frequency dielectric substrate patterns according to any one of claims 1 to 2, characterized in that, When the thickness of the microwave high-frequency dielectric substrate is 0.254 mm and it has process lines and inner groove cross-sections for gold cutting, the laser parameters are divided into two cutting stages: the first cutting speed is 400 mm / s to 450 mm / s, the power is 15.2 W to 15.8 W, the number of galvanometer scans is 55 to 60, and the focal length shift is 0 μm; the second cutting speed is 700 mm / s to 800 mm / s, the power is 15.5 W to 16.2 W, the number of galvanometer scans is 25 to 30, and the focal length shift is 120 μm.

Images