Computer-based integrated circuit board surface laser cutting power control system

Abstract

The invention discloses an integrated circuit board surface laser cutting power control system based on a computer, and relates to the technical field of circuit board cutting. A light path integration module comprises a composite laser source, a light path switching unit and a self-adaptive focusing unit, and a process execution module can switch an ultraviolet cutting unit, a micro water guide cutting unit and an invisible cutting unit to be in butt joint with the light path integration module according to the cutting requirement of a circuit board; through precise matching of the composite laser source and the multiple cutting units, full-coverage machining of different types of integrated circuit boards is achieved; meanwhile, the response time and the positioning deviation of switching are reduced through the coarse positioning and fine calibration logic of the light path switching unit and the universal focusing design of the self-adaptive focusing unit, and the stability and the accuracy of laser cutting under different schemes are ensured in cooperation with secondary exclusive focusing of the cutting unit. The problems of low efficiency, error accumulation and the like caused by traditional multi-device switching machining are solved, and the overall adaptability and production efficiency of circuit board cutting are improved.

Description

Technical Field

[0001] This invention belongs to the field of circuit board cutting technology, specifically a computer-based power control system for laser cutting of integrated circuit board surfaces. Background Technology

[0002] In the field of integrated circuit board processing, laser cutting has become the mainstream processing method due to its core advantages of high precision and low damage. Currently, the industry has formed three main laser cutting technology solutions: ultraviolet laser cold cutting, micro-water-guided laser cutting, and stealth cutting. In existing technologies, each cutting solution relies on a dedicated laser source, cutting unit, and supporting optical path system, forming a relatively independent processing equipment system. The appropriate single equipment must be selected for production based on the material, thickness, and processing precision requirements of the circuit board.

[0003] However, existing technologies have the following limitations: On the one hand, a single laser cutting device can only be adapted to the processing needs of specific types of integrated circuit boards. When facing different scenarios such as conventional circuit boards, flexible circuit boards, and high-precision packaging substrates, different processing equipment needs to be replaced, which not only increases the equipment investment cost, but also causes production process interruption due to equipment switching, resulting in low processing efficiency. On the other hand, the optical path systems of different devices are independent of each other and lack a unified optical path integration and switching mechanism. Positioning deviations are prone to occur during equipment switching, and the focusing parameters of each device need to be adjusted separately, which causes the cutting accuracy to be affected by the accumulation of errors, making it difficult to balance processing adaptability, stability and production efficiency.

[0004] To address the aforementioned technical problems, this invention provides a computer-based power control system for laser cutting of integrated circuit board surfaces. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art; to this end, the present invention proposes a computer-based power control system for laser cutting of integrated circuit board surfaces.

[0006] To achieve the above objectives, a first aspect of the present invention provides a computer-based power control system for laser cutting of integrated circuit board surfaces, comprising an optical path integration module, a process execution module, and a monitoring and control module; The optical path integration module is used to output a laser beam according to the circuit board cutting scheme; the circuit board cutting scheme includes ultraviolet cutting scheme, micro-water-conducting cutting scheme and stealth cutting scheme; The process execution module is used to switch the corresponding laser cutting unit according to the circuit board cutting scheme to execute the circuit board cutting scheme; wherein, the laser cutting unit includes an ultraviolet cutting unit, a micro water-conducting cutting unit, and a stealth cutting unit; The monitoring and control module is used to switch monitoring sensors according to the circuit board cutting scheme and adjust the laser beam output by the optical path integration module according to the monitoring data of the monitoring sensors; among them, the monitoring sensors include infrared temperature sensors, plasma monitoring sensors and OCT modules.

[0007] In one possible implementation, the optical path integration module includes a composite laser source, an optical path switching unit, and an adaptive focusing unit; The composite laser source integrates several types of lasers, including nanosecond-level ultraviolet lasers, infrared / green pulsed lasers, and femtosecond / picosecond infrared lasers; The optical path switching unit switches the light source through a high-speed electronically controlled mirror assembly and an acousto-optic modulator. The adaptive focusing unit is used to automatically adjust the focusing parameters of the switched laser beam.

[0008] In one possible implementation, the corresponding laser cutting unit is switched according to the circuit board cutting scheme to execute the circuit board cutting scheme, including: Select the target cutting unit from the laser cutting unit according to the circuit board cutting plan; Switch the target cutting unit to interface with the optical path integration module, and use the laser beam output by the optical path integration module to complete the cutting of the integrated circuit board.

[0009] In one possible implementation, adjusting the laser beam output by the optical path integration module based on monitoring data from the monitoring sensor includes: Extract the optimal values ​​corresponding to the monitoring data; where the monitoring data includes temperature data, plasma signal intensity, or OCT scan signal intensity; When the monitoring data deviates from the corresponding optimal value and the data deviation exceeds the preset deviation threshold, the laser beam is adjusted according to the data deviation.

[0010] In one possible implementation, a workbench and an environmental control module are also included; The workbench is used to position and fix the integrated circuit board; The environmental control module is used to ensure the stability of the processing environment.

[0011] In one possible implementation, switching the monitoring sensor according to the circuit board cutting scheme includes: The main sensor and auxiliary sensor are selected based on the circuit board cutting plan; Switch between the main sensor and the auxiliary sensor to monitor the cutting process. Use the selected main sensor to collect main data and the auxiliary sensor to collect auxiliary data.

[0012] In one possible implementation, adjusting the laser beam output by the optical path integration module based on monitoring data from the monitoring sensor includes: Extract the monitoring data set; the monitoring data set includes master data and auxiliary data; The laser beam output from the optical path integration module is adjusted based on the monitoring data set in order to improve the adjustment accuracy of the laser beam through auxiliary data.

[0013] In one possible implementation, when the circuit board cutting scheme is an ultraviolet cutting scheme, the laser beam output by the optical path integration module is adjusted based on the monitoring data set, including: Extract the master data and auxiliary data from the monitoring data set; the master data is temperature data, and the auxiliary data is OCT scan results, which include the material reference thickness and the actual cutting depth. Based on the temperature-depth mapping model of the circuit board cutting layer, the optimal temperature value of the actual cutting depth is matched through the temperature-depth mapping model, and the optimal temperature is obtained by expanding from the optimal temperature value as the center. When the temperature data deviates from the corresponding optimal temperature and the temperature deviation exceeds the preset temperature threshold, the laser beam is adjusted according to the data deviation.

[0014] In one possible implementation, when the circuit board cutting scheme is a micro-water-conducting cutting scheme, the laser beam output by the optical path integration module is adjusted based on the monitoring data set, including: Extract the main data and auxiliary data from the monitoring data set; the main data is temperature data, and the auxiliary data is environmental data one. The temperature data includes the micro water column temperature and material surface temperature of the cutting area, and the environmental data one includes air pressure data and humidity data. The plasma signal intensity is corrected once using temperature data, and then corrected a second time using environmental data to obtain the corrected plasma signal intensity. When the corrected plasma signal intensity deviates from the corresponding optimal signal intensity and the intensity deviation exceeds the preset deviation threshold, the laser beam and water pressure are adjusted according to the intensity deviation.

[0015] In one possible implementation, when the circuit board cutting scheme is a stealth cutting scheme, the laser beam output by the optical path integration module is adjusted based on the monitoring data set, including: Extract the main data and auxiliary data from the monitoring data set; the main data is the scan signal data, and the auxiliary data is environmental data II, which includes temperature data and humidity data. The scanning signal data is corrected using environmental data 2, and the corrected scanning signal data is compared with the reference signal of the metamorphic layer. When the corrected scanning signal data deviates from the corresponding optimal scanning signal and the signal deviation exceeds the preset deviation threshold, the laser beam is adjusted according to the signal deviation.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. The optical path integration module of this invention includes a composite laser source integrating a nanosecond-level ultraviolet laser, an infrared / green pulsed laser, and a femtosecond / picosecond infrared laser. Light source switching is achieved through an optical path switching unit composed of a high-speed electrically controlled reflector group and an acousto-optic modulator, with the adaptive focusing unit adjusting the focusing parameters. The process execution module can switch between an ultraviolet cutting unit, a micro-water-conducting cutting unit, and a stealth cutting unit, depending on the circuit board cutting requirements, to achieve the corresponding cutting scheme. This invention breaks through the limitations of traditional single laser cutting schemes. Through precise matching of the composite laser source and multiple cutting units, it achieves full-coverage processing of different types of integrated circuit boards. Simultaneously, the coarse positioning and fine calibration logic of the optical path switching unit and the universal focusing design of the adaptive focusing unit significantly reduce the response time and positioning deviation during scheme switching. Combined with the secondary dedicated focusing of the cutting unit, it ensures the stability and accuracy of laser cutting under different schemes, solving the problems of low efficiency and error accumulation caused by traditional multi-device switching processing, and improving the overall adaptability and production efficiency of integrated circuit board cutting.

[0017] 2. In this invention, the monitoring and control module can select the main sensor and auxiliary sensor according to the circuit board cutting scheme, collect a monitoring data set containing main data and auxiliary data, and adjust the laser beam output by the optical path integration module based on the data set. This invention breaks through the limitations of traditional single data monitoring and power adjustment, and achieves precise closed-loop power adjustment through the synergistic effect of main and auxiliary data: In ultraviolet cutting, auxiliary data can trigger the switching of temperature depth mapping model, solve the power adjustment deviation caused by sudden changes in the thermal conductivity of multilayer composite boards, and verify the cutting depth to ensure the effectiveness of adjustment; In micro-water conduction cutting, auxiliary data is used to perform secondary correction of plasma signal intensity, eliminating signal distortion caused by environmental interference such as water temperature, air pressure, and humidity; In stealth cutting, auxiliary data is used to compensate for the influence of the environment on OCT scanning signal, ensuring the accuracy of metamorphic layer monitoring; The fusion of main and auxiliary data not only makes up for the lag or one-sidedness of single data monitoring, but also improves the response speed and accuracy of power adjustment through multi-dimensional data verification, effectively avoiding problems such as incomplete cutting, edge burrs, and abnormal metamorphic layers, and optimizing the cutting quality of integrated circuit boards. Attached Figure Description

[0018] 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the system principle of the laser cutting power control system for the surface of an integrated circuit board in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the steps of adjusting the laser beam based on master data and auxiliary data in Embodiment 2 of the present invention. Detailed Implementation

[0020] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0021] Example:

[0022] Please see Figure 1 The first aspect of the present invention provides a computer-based power control system for laser cutting of integrated circuit board surfaces, including an optical path integration module, a process execution module and a monitoring and control module; The optical path integration module is used to output a laser beam according to the circuit board cutting scheme; the process execution module is used to switch the corresponding laser cutting unit to execute the circuit board cutting scheme according to the circuit board cutting scheme; the monitoring and control module is used to switch the monitoring sensor according to the circuit board cutting scheme and adjust the laser beam output by the optical path integration module according to the monitoring data of the monitoring sensor.

[0023] The optical path integration module includes a composite laser source, an optical path switching unit, and an adaptive focusing unit.

[0024] The composite laser source integrates lasers required for various cutting schemes, such as nanosecond-level ultraviolet lasers for ultraviolet laser cutting, infrared / green pulse lasers for micro-water-conducting cutting, and femtosecond / picosecond infrared lasers for stealth cutting; the composite laser source can output the corresponding laser beam according to the determined circuit board cutting scheme.

[0025] The optical path switching unit employs a combination of a high-speed electrically controlled mirror assembly and an acousto-optic modulator to achieve light source switching, effectively reducing both response time and positioning deviation. The high-speed electrically controlled mirror assembly can use a two-axis high-precision piezoelectric ceramic driven mirror (response frequency ≥ 1kHz). By rapidly adjusting the angle of the mirrors, the high-speed electrically controlled mirror assembly changes the propagation direction of the laser beams output from different laser sources, achieving rapid switching and initial positioning of the optical path. The acousto-optic modulator (AOM) can use a lithium niobate crystal as the acousto-optic interaction medium. The acousto-optic modulator performs intensity calibration and micro-correction of the propagation direction of the switched laser beam, while also possessing the function of rapidly switching the laser on and off, avoiding mutual interference between beams from different laser sources during the optical path switching process.

[0026] In its operation, the optical path switching unit first generates a switching command based on the selected circuit board cutting scheme. Simultaneously, it retrieves the angle reference parameters of the high-speed electronically controlled mirror assembly corresponding to the laser source and the driving frequency parameters of the acousto-optic modulator from the database. The high-speed electronically controlled mirror assembly adjusts the mirror angle according to the angle reference parameters, ensuring that the laser beam, after reflection, accurately points to the incident port of the adaptive focusing unit, completing the initial optical path switching. Then, the acousto-optic modulator starts working according to the driving frequency parameters. On one hand, it uses the acousto-optic diffraction effect to slightly correct the propagation direction of the initially switched laser beam, further reducing optical path positioning deviation and ensuring that the laser beam is completely incident along the optical axis of the adaptive focusing unit. On the other hand, the AOM (Adaptive Oscillator) is in the conducting state, effectively cutting off beams from other non-target laser sources and preventing stray light from interfering with the current cutting process.

[0027] The optical path switching unit can reduce response time and positioning deviation. Firstly, traditional single-electro-controlled mirror switching requires simultaneous angle adjustment and light intensity control, resulting in a cumbersome process. This solution achieves parallel optimization through functional division of labor. The electro-controlled mirror group is only responsible for rapid angle adjustment, while the AOM simultaneously completes light intensity control and interference isolation, eliminating the need for additional waiting time for light intensity stabilization and reducing switching response time. Simultaneously, the preset reference parameters in the database avoid repeated adjustments during the switching process, further improving response efficiency. Secondly, a two-stage positioning logic of coarse positioning + fine calibration is adopted. The high-speed electro-controlled mirror group completes the coarse positioning of the optical path, while the AOM achieves fine calibration through precise control of acousto-optic diffraction, correcting minor angular deviations in the coarse positioning process.

[0028] The adaptive focusing unit automatically adjusts the focusing parameters through a high-precision objective lens to ensure that various cutting schemes can be achieved. For example, it can focus to a spot size of 15μm for ultraviolet laser cold cutting; focus to a spot size of 80μm for micro-water-conducting laser cutting; and focus to a preset depth inside the circuit board for stealth cutting.

[0029] The process execution module is used to switch the corresponding laser cutting unit according to the circuit board cutting requirements to complete the circuit board surface cutting operation. Each laser cutting unit is connected to the optical path integration module through a mechanical device (such as a multi-axis servo robotic arm). The laser cutting units include ultraviolet cutting units, micro-water-conducting cutting units, and stealth cutting units.

[0030] When cutting circuit boards using an ultraviolet laser cutting solution, the ultraviolet cutting unit and the optical path integration module are first connected. The nanosecond-level ultraviolet laser in the optical path integration module outputs a laser beam, which is focused by the quartz lens group in the ultraviolet cutting unit onto a spot with a target diameter (≤20um) to complete the cutting operation on the surface of the circuit board.

[0031] When cutting circuit boards using the micro-water-guided laser cutting solution, the micro-water-guided cutting unit and the optical path integration module are first connected. The infrared / green pulsed laser in the optical path integration module outputs a laser beam, which is coupled with the stable water jet generated by the high-pressure water cavity in the micro-water-guided cutting unit. Finally, the laser beam is focused by a sapphire nozzle onto a spot with a target diameter (50um to 100um) to complete the cutting operation on the circuit board surface.

[0032] When cutting circuit boards using the stealth cutting solution, the stealth cutting unit and the optical path integration module are first connected. The femtosecond / picosecond infrared laser in the optical path integration module outputs a laser beam, which is focused into the inside of the circuit board by the laser focusing device in the stealth cutting unit to form a uniform modified layer. With the help of the extended adhesive film stretching device and the laser-assisted separation component, stress-free separation can be achieved.

[0033] It is worth noting that the optical path integration module is equipped with an adaptive focusing unit, which focuses the laser beam to different target diameters for different cutting schemes. After the optical path integration module is connected to the laser cutting unit in the process execution module, the laser beam output by the optical path integration module, after being focused once, will be focused a second time by the laser cutting unit. The first focusing is a general-purpose focusing, a basic adaptation for the three cutting schemes, and cannot be customized for the specific needs of each cutting scheme; the second focusing, based on the basic adaptation, completes the scheme-specific focusing to meet specific requirements.

[0034] Furthermore, during the switching between various cutting schemes, the mechanical movements of the high-speed electronically controlled reflector group and the acousto-optic modulator in the optical path switching unit may introduce slight optical path deviations. Although the adaptive focusing unit can perform preliminary calibration, it cannot completely eliminate the impact of deviations on cutting accuracy. Secondary focusing can eliminate the impact.

[0035] The monitoring and control module includes a variety of monitoring sensors and environmental sensing units. The monitoring sensors include infrared temperature sensors, plasma monitoring sensors, and OCT modules. The environmental sensing units integrate temperature sensors, humidity sensors, and air pressure sensors.

[0036] The monitoring and control module controls the precise alignment of each monitoring sensor through an electric switching device to collect relevant monitoring data; at the same time, the environmental sensing unit is used to collect environmental data and calibrate the monitoring data using the environmental data.

[0037] It should be noted that the electric switching device uses a servo motor or stepper motor to drive the sensors to collect monitoring data. The sensors can be fixed on a sensor bracket, and each sensor can be independently controlled to achieve synchronous monitoring by multiple sensors.

[0038] During ultraviolet cutting, an infrared temperature sensor collects temperature data of the cutting area at a preset frequency. This temperature data is compared with a preset optimal temperature. If the temperature deviation deviates from the preset optimal temperature, the laser power is adjusted based on the temperature deviation and a PID algorithm. It should be noted that the optimal temperature refers to the temperature that ensures cutting quality and can be determined through extensive experimentation; the temperature difference threshold is set empirically and can be set to 5℃.

[0039] During micro-water-guided cutting, a plasma monitoring sensor collects the plasma signal intensity of the cutting area in real time. This plasma signal intensity is compared with a preset optimal signal intensity. If the plasma signal intensity deviates from the optimal signal intensity, and the deviation exceeds a preset intensity deviation threshold, the laser power is adjusted according to a preset intensity deviation-power linkage model. It should be noted that the optimal signal intensity refers to the signal intensity corresponding to the optimal cutting quality, which can be determined through extensive experimentation. The intensity deviation-power linkage model is used to determine the laser beam power adjustment ratio based on the signal intensity deviation, and adjusts the current laser power accordingly.

[0040] During stealth cutting, the OCT module continuously acquires tomographic image data of the circuit board. It extracts the features of the altered layer using existing image analysis algorithms, including boundary contours and thickness data. These features are then converted into scanning signal intensity. The scanning signal intensity is compared with a preset scanning signal reference intensity. If the scanning signal intensity is not within the reference range, a fuzzy control algorithm is used to adjust the laser frequency. It should be noted that the scanning signal reference intensity is the OCT scanning signal intensity under the reference state parameters of the altered layer corresponding to the circuit board, determined through extensive experimentation. These reference state parameters correspond to the optimal cutting quality.

[0041] The system of this invention also includes a worktable and an environmental control module. The worktable, used for positioning and fixing integrated circuit boards, includes a vision positioning unit and a fixing device. The vision positioning unit achieves precise positioning of the circuit board through multiple adjustable-angle lenses. The environmental control module ensures the stability of the processing environment and the continuity of the processing process. It controls the temperature, humidity, etc., of the processing environment, forming a closed-loop control with the environmental sensing unit to ensure processing stability.

[0042] Example 2: Please refer to Figure 2 , Figure 2 This is a schematic diagram illustrating the steps of adjusting the laser beam based on master data and auxiliary data.

[0043] Ultraviolet cold cutting utilizes an ultraviolet laser beam with a wavelength of less than 400nm to focus on the material surface and directly break the molecular chemical bonds, achieving "cold" removal of the material. It is currently the most widely used technical solution for surface cutting of integrated circuit boards. Its core feature is that the heat-affected zone is extremely small, avoiding the thermal deformation and carbonization problems of traditional infrared laser cutting.

[0044] The ultraviolet cold cutting module includes: 1) Light source and optical path: a nanosecond-level ultraviolet laser (common wavelength 355nm) with an adjustable output power of 1-20W is selected. The laser beam is focused into a tiny spot with a diameter of less than 20um through a beam expander, reflector and focusing lens group, which acts on the surface of the circuit board; 2) Power control strategy: an infrared temperature sensor is equipped to monitor the temperature of the cutting area in real time, and the laser single pulse energy is dynamically adjusted by combining a PID algorithm to avoid carbonization caused by excessive power.

[0045] In power control strategies, infrared temperature measurement is a post-processing monitoring method, and PID algorithm compensation has a certain lag, which can easily lead to temporary incomplete cutting or edge burrs. Moreover, this strategy only indirectly judges the cutting effect through temperature and cannot directly obtain cutting depth data. When cutting multi-layer composite boards, if the thermal conductivity of one layer of material changes abruptly, temperature judgment may be misjudged, resulting in power adjustment deviations.

[0046] In this invention, the power adjustment strategy during the ultraviolet cutting process is as follows: 1) First, extract the core parameters of the circuit board to be cut, such as material type and target cutting depth. Then, extract the temperature-depth mapping model from the database based on the core parameters. This temperature-depth mapping model is the core benchmark built through a large number of process experiments in the early stage, which can provide a basis for adjusting the laser power according to the cutting temperature in the later stage.

[0047] 2) The infrared temperature sensor collects the temperature data of the cutting area in real time at a preset high-frequency sampling frequency of 10kHz; at the same time, the OCT module is activated to perform a shallow scan of the light spot and the surrounding area to obtain the material reference thickness and actual cutting depth of the current cutting layer in the cutting area.

[0048] 3) Compare the temperature data collected by the infrared temperature sensor with the optimal temperature value corresponding to the cutting depth of the current cutting layer in the temperature depth mapping model; if the temperature deviation exceeds the preset temperature difference threshold, it is determined that power adjustment is required, and the laser pulse energy is quickly adjusted by the PID algorithm to complete the power adjustment.

[0049] 4) After the OCT module collects the material reference thickness and the actual cutting depth, it determines whether the depth mapping model needs to be switched based on the material reference thickness. If so, it calls the temperature-depth mapping model of the current material from the database and adjusts the laser power based on the temperature-depth mapping model.

[0050] The need to switch the depth mapping model can be determined by continuously analyzing the data collected by the OCT module. For example, if a circuit board has two layers of material A and B, when cutting the first layer A, the temperature-depth mapping model of layer A is called, and the OCT module can collect the reference thickness of the material of layer A. If the OCT module detects a sudden change in the reference thickness of the material during the cutting process, it means that layer B has been cut. At this time, the temperature mapping model needs to be immediately replaced with the temperature-depth mapping model corresponding to layer B.

[0051] It is worth noting that if the integrated circuit board is a multi-layered composite material, and the target cutting depth penetrates through multiple layers, the ultraviolet laser will cut the upper layer first and then the lower layer. This can cause residual heat from the upper layer to affect the accuracy of the temperature data collected by the infrared temperature sensor in the cutting area, potentially leading to over-adjustment of the laser power. To solve this problem, it is necessary to set a reasonable temperature difference threshold, such as 5℃, while also ensuring that the OCT module accurately measures the temperature data of the core cutting area to minimize the cumulative effect of heat.

[0052] In this invention, the construction of the temperature-depth mapping model can refer to the following steps: Preset experimental variables and select mainstream materials for integrated circuit boards, such as FR4, PI, composite boards, and thick copper PCBs. Group them according to thickness gradients (50μm, 100μm, 200μm, 300μm, 500μm). Set different combinations of laser power (1-20W, step size 1W) and pulse width (1-20ns, step size 2ns) parameters for each group. Set other processing conditions (such as feed rate, temperature, humidity, etc.) to be fixed.

[0053] For each parameter combination, an ultraviolet cutting test is initiated, and steady-state temperature data of the cutting area is collected in real time using an infrared temperature sensor (sampling frequency 10kHz). This steady-state temperature data excludes unstable data during the initial heating and final cooling stages. Simultaneously, the actual cutting depth is collected through an OCT module. Each parameter combination is tested at least three times, and the average of the steady-state temperature data and the actual cutting depth is taken as the raw data to avoid experimental errors.

[0054] The raw data is preprocessed to remove outliers. A temperature-depth mapping model is then fitted using a polynomial fitting method to fit the temperature data and cutting depth data of the same material at different thicknesses. The obtained temperature-depth mapping models for various materials are stored in a database.

[0055] It should be noted that the independent variables of the temperature-depth mapping model are the material thickness and cutting depth data, and the dependent variable is the temperature data. Of course, temperature-depth mapping models can also be established separately for materials of different thicknesses. In this case, the independent variable of the temperature-depth mapping model is the cutting depth data, and the dependent variable is the temperature data.

[0056] This solution addresses the lag issue in infrared thermometry by utilizing high-frequency sampling and a PID algorithm for rapid adjustment, shortening the response time to temperature deviations. Simultaneously, OCT's synchronous depth monitoring enables real-time verification of power adjustment effectiveness, ensuring timely and accurate power regulation and effectively preventing brief incomplete cuts or edge burrs. It also resolves the deviation problem caused by abrupt changes in thermal conductivity. When processing multi-layer composite boards (such as FR4 and PI composite boards), if laser cutting reaches different material interfaces, traditional single-temperature monitoring can distort the temperature signal due to sudden changes in thermal conductivity, leading to power adjustment deviations. In this solution, the material reference thickness acquired by OCT can identify material interface switching in real time, synchronously triggering the temperature-depth mapping model update mechanism. This ensures that the optimal temperature setting is more closely aligned with the material characteristics of the current cutting layer, avoiding temperature judgment errors caused by sudden changes in thermal conductivity, thereby eliminating power adjustment deviations and ensuring the consistency of cutting depth across all layers of the multi-layer composite board.

[0057] Micro-water-guided laser cutting is a composite processing technology that combines laser and water. It uses a micro-water column formed by high-pressure pure water as a laser transmission channel. The laser beam is totally reflected within the water column to the material surface, achieving non-contact cutting of integrated circuits. Its core advantage is that cooling and cutting are synchronized, making it particularly suitable for cutting the surface of ultra-thin, easily deformable flexible circuit boards.

[0058] The micro-water-guided laser cutting module includes: 1) Laser-water column coupling: an infrared or green laser is selected as the light source. The laser beam is coupled to the high-pressure water cavity through a focusing lens. The water cavity sprays out a micro-water column with a diameter of 50-100um through a precision nozzle. The laser is totally reflected in the water column and focused on the surface of the circuit board; 2) Power and water pressure linkage control strategy: equipped with a plasma monitoring sensor, the plasma signal of the cutting area is collected in real time, and the power and water pressure are dynamically adjusted. When the power is too high, the water pressure is increased to enhance the cooling effect, and when the power is too low, the water pressure is reduced to avoid energy loss.

[0059] Plasma signals are not only susceptible to the temperature of the micro-water column and the surface temperature of the material, but also to factors such as air pressure and humidity in the processing environment. Fluctuations in air pressure can cause changes in the plasma diffusion rate, while increased humidity can weaken the plasma intensity, leading to misjudgments in power adjustment and affecting cutting accuracy.

[0060] In this invention, the power control strategy during the micro-water-guided cutting process is as follows: 1) First, determine the core parameters of the circuit board to be cut, such as material type and preset cutting path. Then, call the matching temperature-signal correction model from the database. The temperature-signal intensity correction model is built based on a large number of experiments. It expresses the mapping relationship between the micro water column temperature and material surface temperature in the cutting area and the plasma signal intensity deviation.

[0061] 2) The plasma monitoring sensor collects the plasma signal intensity in the laser-material interaction area in real time at a high sampling frequency of 20kHz. The peak intensity of the plasma signal directly reflects the effective utilization rate of laser energy and the material removal rate, and is the core basis for determining whether the power needs to be adjusted.

[0062] 3) The infrared temperature sensor synchronously collects temperature data, including the water temperature of the micro water column in the cutting area and the surface temperature of the material. The temperature data is then fed into the temperature-signal intensity correction model to correct the plasma signal intensity collected by the plasma sensor. This can eliminate the signal deviation caused by water temperature interference and make the plasma signal intensity more realistic.

[0063] 4) The environmental sensing unit collects environmental data of the cutting environment in real time, including air pressure data and humidity data. The sampling frequency can be set to 1kHz. Based on the environmental-signal strength correction model in the database, the plasma signal strength after the first correction is compensated for a second time to avoid plasma signal strength distortion caused by environmental fluctuations.

[0064] 5) Compare the corrected plasma signal intensity with the preset signal intensity benchmark value. If the signal intensity deviation exceeds the preset signal deviation threshold, adjust the laser power and micro water column water pressure based on the preset laser power and water pressure adjustment ratio matched with the signal intensity deviation.

[0065] The temperature-signal intensity correction model includes the mapping relationship between temperature data (micro-water column temperature and material surface temperature) and plasma signal intensity deviation. A large amount of experimental data can be obtained first, each containing temperature data and the corresponding plasma signal intensity deviation at that temperature. The temperature-signal intensity correction model can then be constructed through polynomial fitting or training an artificial intelligence model. Similarly, the environment-signal intensity correction model includes the mapping relationship between environmental data (air pressure data and humidity data) and plasma signal intensity. Its construction process is the same as that of the temperature-signal intensity correction model and will not be elaborated further here.

[0066] When obtaining experimental data for constructing temperature-signal intensity correction models or environment-signal intensity correction models, the plasma signal intensity at standard temperature or under standard environment can be tested first. Then, different data gradients can be set to obtain the corresponding plasma signal intensity. The difference between the plasma signal intensity at standard temperature or under standard environment and the plasma signal intensity at standard temperature or under standard environment can be used as the signal intensity deviation.

[0067] In traditional solutions, plasma signals are easily affected by the measurement and cutting environments, leading to misjudgments in power adjustment. This solution provides dual protection through primary correction via infrared thermometry and secondary correction via environmental sensing: infrared thermometry correction eliminates interference from water column temperature changes on the signal, ensuring the signal reflects the true energy-material interaction state; environmental data correction anticipates the effects of air pressure and humidity, correcting for signal deviations before they occur, avoiding the lag of traditional methods that correct after deviations occur, and solving the problem of reduced cutting accuracy caused by environmental interference, ensuring stable micro-water column morphology and precise cutting trajectory.

[0068] Stealth cutting is a processing technology that focuses laser energy on the inside of an integrated circuit board rather than its surface. It breaks the molecular chemical bonds inside the material to form a modified layer, and then separates the material by external force. Its core advantages are no surface damage and a narrow cutting kerf. It is mainly used for cutting wafer-level chip packaging substrates and ultra-thin PCBs.

[0069] The stealth cutting module includes: 1) a light source, which is an infrared femtosecond / picosecond laser (common wavelength 1064nm) with an output power of 5-50W. The laser beam is focused at a preset depth inside the circuit board through a high-precision objective lens to avoid energy acting on the surface; 2) a power control strategy, which uses optical coherence tomography (OCT) to monitor the formation state of the internal metamorphic layer in real time, and combines fuzzy control algorithm to dynamically adjust and control the laser power. When the metamorphic layer is too shallow, the power is increased, and when it is too deep, the power is decreased.

[0070] In power control strategies, OCT scanning generates a large amount of tomographic image data, which requires a certain amount of time for image analysis and feature extraction. This results in the power adjustment response speed (hundreds of microseconds) being slower than the microsecond response of plasma monitoring, making it unsuitable for ultra-high-speed cutting scenarios.

[0071] In this invention, the power control strategy during the stealth cutting process is as follows: 1) First, determine the core parameters of the circuit board to be cut, such as material type, preset cutting thickness, internal structural parameters, etc. Then, call the environment-scanning signal correction model from the database. This correction model is established through a large number of process experiments and covers the deviation law of OCT scanning signals under different temperatures and humidity.

[0072] 2) The OCT module acquires real-time tomographic image data of the circuit board's interior using a high-frequency scanning frequency of 15kHz. This tomographic image data directly reflects the thickness and uniformity of the metamorphic layer. The tomographic image data is synchronously transmitted to the image preprocessing module. First, wavelet transform is used for noise reduction to remove invalid background noise such as tiny impurities within the material. Then, an edge detection algorithm is used to enhance the extraction of metamorphic layer features. Finally, the data is converted into a scanning signal intensity, quickly locking the boundary contour of the metamorphic layer. This compression of image resolution time lays the foundation for rapid power adjustment. The method of converting tomographic image data into scanning signal intensity has been disclosed in existing solutions.

[0073] 3) The environmental sensing unit synchronously collects environmental data of the processing environment, including temperature data and humidity data, with a sampling frequency of 1kHz. This environmental data is substituted into the environmental-scanning signal correction model to compensate for the deviation of the pre-processed OCT scan signal. The deviation caused by environmental fluctuations can be eliminated in advance through model calculation to ensure that the signal truly reflects the state of the metamorphic layer.

[0074] 4) The OCT scan signal, after environmental deviation compensation, is compared with a preset metamorphic layer reference signal. If the signal intensity deviation exceeds a preset signal deviation threshold, the metamorphic layer is determined to be unsatisfactory. Subsequently, a fuzzy control algorithm is used to dynamically adjust the laser output power, achieving preliminary closed-loop power control. It should be noted that the metamorphic layer reference signal corresponds to the optimal signal for the target metamorphic layer thickness and uniformity.

[0075] The environment-scan signal correction model includes the mapping relationship between environmental data (temperature and humidity data) and OCT scan signal intensity deviation. This correction model can also be constructed using a large amount of experimental data; for specific construction procedures, please refer to the construction of the temperature-signal intensity correction model or the environment-signal intensity correction model.

[0076] In traditional solutions, the propagation of OCT lasers is easily affected by ambient temperature and humidity, leading to scanning signal distortion and subsequent misjudgments in power adjustment. This solution uses temperature and humidity data collected by an environmental sensing unit as auxiliary signals, and corrects the OCT scanning signal through a preset correction model. This eliminates signal deviations caused by environmental factors in advance, ensuring that the signal can accurately reflect the state of the metamorphic layer and improving the accuracy of power adjustment.

[0077] It should be understood that the descriptions of technical features, technical solutions, beneficial effects, or similar language in this application do not imply that all features and advantages can be achieved in any single embodiment. Rather, it is understood that the description of a feature or beneficial effect means that a specific technical feature, technical solution, or beneficial effect is included in at least one embodiment. Therefore, the descriptions of technical features, technical solutions, or beneficial effects in this specification do not necessarily refer to the same embodiment. Furthermore, the technical features, technical solutions, and beneficial effects described in this embodiment can be combined in any suitable manner. Those skilled in the art will understand that embodiments can be implemented without one or more specific technical features, technical solutions, or beneficial effects of a particular embodiment. In other embodiments, additional technical features and beneficial effects may be identified in specific embodiments that do not embody all embodiments.

[0078] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any other combination thereof. When implemented using a software program, it can be implemented entirely or partially in the form of a computer program product. This computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device containing one or more servers, data centers, etc., that can be integrated with the medium. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state disks (SSDs)).

[0079] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A computer-based power control system for laser cutting of integrated circuit board surfaces, characterized in that, It includes an optical path integration module, a process execution module, and a monitoring and control module; The optical path integration module is used to output a laser beam according to the circuit board cutting scheme; wherein, the circuit board cutting scheme includes ultraviolet cutting scheme, micro-water-conducting cutting scheme and stealth cutting scheme; The process execution module is used to switch the corresponding laser cutting unit according to the circuit board cutting scheme to execute the circuit board cutting scheme; wherein, the laser cutting unit includes an ultraviolet cutting unit, a micro water-conducting cutting unit, and a stealth cutting unit; The monitoring and control module is used to switch monitoring sensors according to the circuit board cutting scheme and adjust the laser beam output by the optical path integration module according to the monitoring data of the monitoring sensors; wherein, the monitoring sensors include an infrared temperature sensor, a plasma monitoring sensor and an OCT module.

2. The computer-based integrated circuit board surface laser cutting power control system according to claim 1, characterized in that, The optical path integration module includes a composite laser source, an optical path switching unit, and an adaptive focusing unit; The composite laser source integrates several types of lasers, including nanosecond-level ultraviolet lasers, infrared / green pulse lasers, and femtosecond / picosecond infrared lasers. The optical path switching unit switches the light source through a high-speed electronically controlled reflector group and an acousto-optic modulator. The adaptive focusing unit is used to automatically adjust the focusing parameters of the switched laser beam.

3. The computer-based integrated circuit board surface laser cutting power control system according to claim 1, characterized in that, The appropriate laser cutting unit is switched according to the circuit board cutting plan to execute the circuit board cutting plan, including: Select the target cutting unit from the laser cutting unit according to the circuit board cutting scheme; The target cutting unit is switched to interface with the optical path integration module, and the laser beam output by the optical path integration module is used to complete the cutting of the integrated circuit board.

4. The computer-based integrated circuit board surface laser cutting power control system according to claim 1, characterized in that, Adjusting the laser beam output by the optical path integration module based on the monitoring data from the monitoring sensor includes: Extract the optimal value corresponding to the monitoring data; wherein, the monitoring data includes temperature data, plasma signal intensity, or OCT scan signal intensity; When the monitoring data deviates from the corresponding optimal value and the data deviation exceeds the preset deviation threshold, the laser beam is adjusted according to the data deviation.

5. The computer-based integrated circuit board surface laser cutting power control system according to claim 1, characterized in that, It also includes a workbench and an environmental control module; The workbench is used to position and fix the integrated circuit board; The environmental control module is used to ensure the stability of the processing environment.

6. The computer-based integrated circuit board surface laser cutting power control system according to claim 1, characterized in that, Switching monitoring sensors according to the circuit board cutting scheme includes: The main sensor and auxiliary sensor are selected based on the circuit board cutting plan; The main sensor and the auxiliary sensor are switched to monitor the cutting process. The main sensor is used to collect main data, and the auxiliary sensor is used to collect auxiliary data.

7. The computer-based integrated circuit board surface laser cutting power control system according to claim 6, characterized in that, Adjusting the laser beam output by the optical path integration module based on the monitoring data from the monitoring sensor includes: Extract the monitoring data set; the monitoring data set includes master data and auxiliary data; The laser beam output by the optical path integration module is adjusted based on the monitoring data set, so as to improve the adjustment accuracy of the laser beam through the auxiliary data.

8. The computer-based integrated circuit board surface laser cutting power control system according to claim 7, characterized in that, When the circuit board cutting scheme is an ultraviolet cutting scheme, adjusting the laser beam output by the optical path integration module based on the monitoring data set includes: Extract the main data and auxiliary data from the monitoring data set; wherein, the main data is temperature data, and the auxiliary data is OCT scan results, including the material reference thickness and the actual cutting depth; Based on the temperature-depth mapping model of the circuit board cutting layer, the optimal temperature value of the actual cutting depth is matched through the temperature-depth mapping model, and the optimal temperature is obtained by expanding around the optimal temperature value. When the temperature data deviates from the corresponding optimal temperature and the temperature deviation exceeds the preset temperature threshold, the laser beam is adjusted according to the temperature deviation.

9. The computer-based integrated circuit board surface laser cutting power control system according to claim 7, characterized in that, When the circuit board cutting scheme is a micro-water-guided cutting scheme, adjusting the laser beam output by the optical path integration module based on the monitoring data set includes: Extract the main data and auxiliary data from the monitoring data set; wherein, the main data is temperature data, and the auxiliary data is environmental data one, the temperature data includes the micro water column temperature of the cutting area and the material surface temperature, and the environmental data one includes air pressure data and humidity data; The plasma signal intensity is corrected once using the temperature data, and then corrected a second time using the environmental data to obtain the corrected plasma signal intensity. When the corrected plasma signal intensity deviates from the corresponding optimal signal intensity and the intensity deviation exceeds a preset deviation threshold, the laser beam and water pressure are adjusted according to the intensity deviation.

10. The computer-based integrated circuit board surface laser cutting power control system according to claim 7, characterized in that, When the circuit board cutting scheme is a stealth cutting scheme, adjusting the laser beam output by the optical path integration module based on the monitoring data set includes: Extract the main data and auxiliary data from the monitoring data set; wherein, the main data is the scan signal data, and the auxiliary data is environmental data two, which includes temperature data and humidity data; The scanning signal data is corrected using the second environmental data, and the corrected scanning signal data is compared with the reference signal of the metamorphic layer. When the corrected scanning signal data deviates from the corresponding optimal scanning signal and the signal deviation exceeds a preset deviation threshold, the laser beam is adjusted according to the signal deviation.

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