Ceramic substrate drilling device and control method

Abstract

The invention provides a ceramic substrate drilling device and a control method.The drilling device comprises a workbench, a drilling mechanism, a feeding assembly, an ultrasonic vibration module, a real-time monitoring unit and a control system, and the control system is electrically connected with a driving motor, the feeding assembly, the ultrasonic vibration module and the real-time monitoring unit; the controller is used for receiving monitoring data and controlling each component to operate. Through real-time parameter adjustment of the ultrasonic vibration module, the vibration amplitude and frequency can be dynamically optimized according to the thickness, aperture and cutting force feedback of the ceramic substrate, the mechanical stress in the drilling process is effectively reduced, and the defects of edge breakage, cracks and the like of the substrate are avoided; in combination with visual detection and force feedback of the real-time monitoring unit, the drilling depth and the hole wall quality are monitored in real time, excessive machining or insufficient machining is avoided, and the rate of finished products is increased.

Description

Technical Field

[0001] This invention belongs to the field of ceramic substrate processing technology, and specifically relates to a ceramic substrate drilling device and control method. Background Technology

[0002] Ceramic substrates are electronic component substrates based on ceramic materials such as alumina (Al2O3), aluminum nitride (AlN), and beryllium oxide (BeO). Due to their excellent insulation, high thermal conductivity, high mechanical strength, matching coefficient of thermal expansion with the chip, and good chemical stability, they are widely used in the packaging and interconnection of high-end electronic products such as high-power power electronic modules, semiconductor coolers, lasers, and high-frequency communication devices. In the manufacturing and processing of ceramic substrates, the drilling process is a critical step, requiring the fabrication of through-holes or blind vias of different diameters and depths to meet the requirements of subsequent wire connections and component mounting.

[0003] Currently, there are two main methods for drilling ceramic substrates: mechanical drilling and laser drilling. Mechanical drilling involves directly cutting the ceramic substrate using a high-speed rotating carbide or diamond-coated drill bit, as exemplified by the drilling equipment disclosed in CN202421340741.X and CN202422437297.X. Laser drilling utilizes a high-energy-density laser beam (such as a CO2 laser or an ultraviolet laser) to melt and vaporize the ceramic substrate, thus creating holes, as exemplified by the drilling equipment disclosed in CN202010393369.9 and CN202410303513.3.

[0004] Mechanical drilling is relatively efficient, with low equipment costs and simple operation, but it has significant problems. For example, the drilling equipment disclosed in CN202422437297.X suffers from stress concentration during drilling due to the high hardness (Mohs hardness can reach 9 or above) and brittleness of ceramic materials, leading to defects such as chipping and cracking of the substrate and a low yield (usually below 80%). Furthermore, the drill bit wears out quickly and requires frequent replacement, increasing production costs and reducing processing efficiency. Therefore, improvements are necessary. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the first aspect of the present invention is to provide a drilling apparatus for ceramic substrates. The second aspect, based on the same inventive concept, also provides a control method based on the aforementioned drilling apparatus for ceramic substrates.

[0006] In this embodiment of the invention, a ceramic substrate drilling device includes a worktable, a drilling mechanism, a feed assembly, an ultrasonic vibration module, a real-time monitoring unit, and a control system. The worktable is used to support and fix the ceramic substrate to be processed. The drilling mechanism includes a spindle, a drive motor, and a drill bit. The drive motor is connected to the spindle and drives the spindle to rotate the drill bit. The feed assembly drives the spindle to move the drill bit vertically for drilling. The ultrasonic vibration module is sleeved outside the spindle, and the vibration frequency and amplitude of the ultrasonic vibration module are adjustable. The real-time monitoring unit includes a vision camera, a force sensor, and a displacement sensor. The vision camera is used to capture images of the drilling area. The force sensor is located between the drilling mechanism and the feed assembly to detect the cutting force during the drilling process. The displacement sensor is used to detect the feed displacement of the spindle. The control system is electrically connected to the drive motor, the feed assembly, the ultrasonic vibration module, and the real-time monitoring unit, respectively, and is used to receive monitoring data and control the operation of each component.

[0007] The control method of this invention, based on the above-described ceramic substrate drilling device, includes the following steps:

[0008] S1: Parameter settings: Input the Vickers hardness Hv, thickness H, target hole diameter D, and drilling depth L of the ceramic substrate. The control system will automatically match the initial processing parameters based on the input parameters, including spindle speed n, initial feed speed v0, initial ultrasonic amplitude A0, initial ultrasonic frequency f0, negative pressure pump suction P0, and high-pressure nozzle air pressure Q0.

[0009] S2: Substrate positioning. The ceramic substrate is placed on the worktable. The control system controls the positioning block of the positioning component to move and perform circumferential positioning of the substrate. The pressure sensor detects the clamping force. When the clamping force reaches the preset value F1=0.1×Hv×D, the positioning block stops moving. At the same time, the negative pressure pump starts and the ceramic substrate is adsorbed and fixed through the negative pressure adsorption hole.

[0010] S3: Staged drilling process. The control system divides the machining process into three stages according to the drilling depth and dynamically adjusts the parameters.

[0011] S31: Stage 1, Inlet Section: Start the drive motor, the spindle rotates at speed n, the feed assembly feeds at 80% of speed v0, the ultrasonic vibration module operates at 1.2 times amplitude A0 and frequency f0, the high-pressure air nozzle sprays gas at 1.1 times air pressure Q0 to avoid inlet edge breakage, and the negative pressure pump suction P0 adsorbs waste debris;

[0012] S32: Phase Two, Mid-Stage: Feed speed increased to v0, ultrasonic amplitude adjusted to A0, frequency maintained at f0, high-pressure nozzle pressure adjusted to Q0, negative pressure pump suction increased to 1.2 times P0, enhancing chip removal effect;

[0013] S32: Stage 3, Outlet Section: Feed speed is reduced to 0.6 times v0, ultrasonic amplitude is adjusted to 1.1 times A0, frequency is increased to 1.1 times f0, high-pressure nozzle pressure is increased to 1.2 times Q0 to avoid outlet cracks, and negative pressure pump suction P0 adsorbs waste.

[0014] S4: Real-time adjustment. During each stage of machining, the force sensor detects the cutting force F in real time. If F > 1.2 times the initial cutting force reference value F0, the control system adjusts the ultrasonic amplitude to increase to A1, where A1 > A0, and simultaneously reduces the feed speed to v1, where v1 < v0. If F < 0.8 times the initial cutting force reference value F0, the ultrasonic amplitude is adjusted to decrease to A2, where A2 < A0, and simultaneously the feed speed is increased to v2, where v2 > v0. The displacement sensor detects the spindle feed displacement s in real time. When the displacement reaches the drilling depth L, the control system controls the feed assembly to stop feeding, and the spindle stops rotating.

[0015] S5: Quality inspection. The vision camera captures images of the hole after drilling is completed. The image processor analyzes the hole wall roughness Ra, hole diameter deviation ΔD, and chipping edge width W. If Ra ≤ preset roughness, ΔD ≤ preset hole diameter deviation, and W ≤ preset chipping edge width, the processing is deemed qualified. If it is unqualified, the control system records the unqualified parameters and prompts for adjustment of the processing parameters.

[0016] S6: Material handling, negative pressure pump shut down, positioning component released, ceramic substrate removed, drilling process completed.

[0017] Compared with the prior art, the advantages of the superior technical solution of the present invention include:

[0018] 1. This invention uses real-time parameter adjustment of the ultrasonic vibration module to dynamically optimize the vibration amplitude and frequency based on the ceramic substrate thickness, hole diameter, and cutting force feedback, effectively reducing mechanical stress during drilling and preventing defects such as chipping and cracking of the substrate; combined with the visual inspection and force feedback of the real-time monitoring unit, the drilling depth and hole wall quality are monitored in real time to avoid over-processing or under-processing and improve the yield.

[0019] 2. By adding an ultrasonic vibration module, the high-frequency vibration causes periodic separation between the drill bit and the ceramic substrate, shortening the cutting contact time and reducing frictional resistance. This not only prevents cracks in the substrate due to continuous stress concentration but also reduces the wear rate of the drill bit, decreasing the frequency of drill bit replacement and lowering consumable costs. Furthermore, the vibration can break ceramic debris into finer particles, reducing hole wall scratches and hole diameter deviations caused by debris accumulation in the hole. Periodic separation reduces frictional heat generation, while vibration assists in heat dissipation, lowering the temperature in the drilling area and preventing phase changes and performance degradation of the ceramic material caused by high temperatures (such as decreased thermal conductivity of the aluminum nitride substrate).

[0020] 3. The chip removal mechanism integrated in this invention achieves rapid discharge of ceramic chips through the synergistic effect of negative pressure adsorption and high-pressure air blowing, avoiding processing interruptions caused by chip accumulation. Compared with traditional mechanical drilling, it improves processing efficiency. At the same time, the wide range of parameter adjustment of the ultrasonic vibration module (amplitude 5-50μm, frequency 10-60kHz) and the servo drive of the feed component can adapt to the processing of ceramic substrates of different materials (alumina, aluminum nitride, silicon carbide), different thicknesses (0.3-5mm), and different hole diameters (0.1-5mm), without the need to change equipment or make major structural adjustments, thus significantly enhancing processing adaptability.

[0021] 4. This invention introduces calculation models such as the initial cutting force reference value F0, the initial feed rate v0, and the initial ultrasonic amplitude A0 to achieve automatic matching of processing parameters for ceramic substrates of different hardness (such as alumina, aluminum nitride, and silicon carbide) and different drilling sizes (hole diameter 0.1-5mm, depth 0.3-5mm), thus avoiding errors from human experience.

[0022] 5. This invention employs a staged drilling process. In the entry section, reducing the feed rate and increasing the ultrasonic amplitude reduces the entry chipping rate. In the middle section, adjusting the high-pressure nozzle pressure and the negative pressure pump suction optimizes chip removal parameters, reducing the hole wall scratch rate. In the exit section, parameters are adjusted again to reduce the exit crack rate, thereby lowering the overall machining defect rate. Simultaneously, by combining real-time cutting force feedback with a hardness correlation formula, when the hardness of the ceramic substrate changes, fine-tuning parameters (e.g., amplitude ±10%, feed rate ±15%) maintains machining stability without requiring resetting basic parameters, adapting to the hardness differences of different batches of ceramic substrates. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a ceramic substrate drilling device according to Embodiment 1.

[0024] The reference numerals in the accompanying drawings include: worktable 10, clearance hole 11, rubber pad 12, drilling mechanism 20, spindle 21, drive motor 22, drill bit 23, feed assembly 30, servo motor 31, ball screw 32, screw sleeve 33, fixing bracket 34, ultrasonic vibration module 40, vibration generator 41, amplitude regulator 42, frequency controller 43, vision camera 51, force sensor 52, displacement sensor 53, control system 60, negative pressure pump 71, high pressure nozzle 72, pipeline 73, air pipe 74, debris collection box 75, positioning assembly 80, pressure sensor 81, positioning block 82, and drive assembly 83. Detailed Implementation

[0025] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0026] Example 1

[0027] This embodiment provides a drilling device for ceramic substrates, such as... Figure 1 As shown, in a preferred embodiment, the drilling device includes a worktable 10, a drilling mechanism 20, a feed assembly 30, an ultrasonic vibration module 40, a real-time monitoring unit, and a control system 60.

[0028] The worktable 10 is used to support and fix the ceramic substrate to be processed. Specifically, it can be fixed by bolt-type pressure plates, quick clamping devices, etc., which are existing technologies. The drilling mechanism 20 includes a spindle 21, a drive motor 22, and a drill bit 23. The drill bit 23 is a diamond-coated carbide drill bit 23. The drive motor 22 is connected to the spindle 21 and is used to drive the spindle 21 to rotate the drill bit 23. This is existing technology and will not be described in detail here. The feed assembly 30 is used to drive the spindle 21 to move the drill bit 23 vertically for drilling operations. Specifically, the feed assembly 30 includes a servo motor 31 (e.g., model HF-KN43J-S100) mounted on a fixed frame 34 and a vertically extending ball screw 32 (e.g., model SFU2005) coaxially connected to the output shaft of the servo motor 31. The ball screw 32 is threadedly connected to a screw sleeve 33 fixed on the drive motor 22. Preferably, the screw sleeve 33 is vertically slidably connected to the fixed frame 34 to ensure the straightness of the spindle 21 feed.

[0029] An ultrasonic vibration module 40 is fitted around the main shaft 21. The vibration frequency and amplitude of the ultrasonic vibration module 40 are adjustable; for example, the vibration amplitude adjustment range of the ultrasonic vibration module 40 is 5-50 μm, and the vibration frequency adjustment range is 10-60 kHz. The ultrasonic vibration module 40 includes a vibration generator 41, an amplitude adjuster 42, and a frequency controller 43. The vibration generator 41 is elastically connected to the main shaft 21 and is used to convert electrical energy into high-frequency mechanical vibration. The amplitude adjuster 42 and the frequency controller 43 are used to adjust the ultrasonic amplitude and ultrasonic frequency, respectively. Specifically, the vibration generator 41 has a ring structure and is fitted around the main shaft 21. It uses a piezoelectric ceramic vibrator (such as model PZT-8) and is elastically connected to the main shaft 21 through three circumferentially evenly distributed spring plates. The spring plates have a pre-compression of 0.2 mm, which ensures vibration transmission efficiency and avoids radial offset of the main shaft 21. Preferably, a cooling sleeve is provided on the outside of the vibration generator 41, and the cooling sleeve is connected to the cooling system through a pipe 73. The amplitude regulator 42 can be an AT-100 type (adjustment accuracy ±0.1μm), and the frequency controller 43 can be an FT-60 type (adjustment accuracy ±10Hz). Both are installed on the side of the mounting bracket 34 and are electrically connected to the control system 60.

[0030] The real-time monitoring unit includes a vision camera 51, a force sensor 52, and a displacement sensor 53. The vision camera 51 is used to capture images of the drilling area. The force sensor 52 is located between the drilling mechanism 20 and the feed assembly 30 to detect the cutting force during the drilling process. The displacement sensor 53 is used to detect the feed displacement of the spindle 21. Specifically, the vision camera 51 is fixed to the right side of the worktable 10 by a bracket. The field of view of the vision camera 51 covers the machining area. The vision camera 51 uses an industrial CCD camera (such as the MV-CE200-10GM type) and is equipped with a macro lens. The vision camera 51 is electrically connected to an image processor. The image processor is used to analyze the images of the drilling area, obtain data on hole wall roughness, hole diameter deviation, and edge chipping, and transmit the data to the control system 60. The force sensor 52 (such as the LFT-100 type) is bolted between the drive motor 22 and the lead screw sleeve 33 to detect the axial cutting force of the spindle 21 in real time. The displacement sensor 53 is mounted on the fixed frame 34 and located above the drive motor 22. It is a laser displacement sensor 53 (such as the LK-G80 type) that obtains feed displacement data by detecting the reflector on the top of the drive motor 22.

[0031] The control system 60 is electrically connected to the drive motor 22, the feed assembly 30, the ultrasonic vibration module 40, and the real-time monitoring unit, respectively, and is used to receive monitoring data and control the operation of each component. The control system 60 includes a PLC controller (such as the FX5U-32MT / ES type) and a touch screen (such as the GT2710-VTBD type). The touch screen is used to input processing parameters (including substrate thickness, hole diameter, and drilling depth) and display the operating status of the equipment. The PLC controller is used to adjust the feed speed of the feed assembly 30 and the parameters of the ultrasonic vibration module 40 in real time based on the feedback data from the force sensor 52 and the displacement sensor 53.

[0032] In another preferred embodiment, the drilling device further includes a chip removal mechanism. The chip removal output control terminal of the control system 60 is connected to the enable terminal of the chip removal mechanism. The surface of the workbench 10 is provided with a plurality of negative pressure adsorption holes (the negative pressure adsorption holes cover the ceramic substrate and its outer periphery). The chip removal mechanism includes a negative pressure pump 71 and a high-pressure air nozzle 72. The negative pressure pump 71 (e.g., VP120 type) is connected to a plurality of negative pressure adsorption holes of the workbench 10 through a plurality of pipes 73. The high-pressure air nozzle 72 is located beside the drill bit 23 (specifically, it can be fixed on the mounting bracket 34) and the air outlet of the high-pressure air nozzle 72 faces the drilling area. The high-pressure air nozzle 72 is connected to a high-pressure air source through an air pipe 74. The pressure adjustment range of the high-pressure air source is 0.4-0.8 MPa. Preferably, the chip removal mechanism further includes a chip collection box 75. The chip collection box 75 is located below the workbench 10 and is connected to the air outlet of the negative pressure pump 71. The chip collection box 75 is provided with a filter screen inside for filtering ceramic chips. More preferably, the filter screen adopts a drawer-type structure, which can be pulled out from the side of the debris collection box 75 for cleaning or replacement; the front of the debris collection box 75 is provided with a transparent observation window for easy observation of debris accumulation.

[0033] During drilling, drill bit 23 generates micron- to millimeter-sized debris as it cuts the ceramic substrate. Some of this debris adheres to the hole wall, the surface of drill bit 23, or accumulates on the substrate surface in the drilling area. During drilling, high-pressure gas (such as compressed air) is injected into the hole and around drill bit 23 via high-pressure nozzle 72. This "active purging" removes debris adhering to the hole wall and the cutting edge of drill bit 23 from its original position, forcing the debris to suspend on the ceramic substrate surface or diffuse to the surrounding area, preventing debris from remaining on the substrate surface due to gravity or electrostatic forces. The debris blown away by the high-pressure gas (either suspended or diffused to the periphery of the substrate) will directly enter the suction coverage area of ​​the negative pressure adsorption holes (because the distribution of the negative pressure adsorption holes covers the periphery of the processing area). At this time, the negative pressure pump 71 can quickly "suck away" these suspended debris and debris on the substrate surface through the negative pressure airflow generated by the negative pressure adsorption holes, preventing the debris from falling back into the holes or onto the surface of the worktable 10, forming a closed loop of "blowing → suspension → adsorption", ensuring that the debris on the surface of the ceramic substrate is effectively removed and significantly improving the chip removal efficiency.

[0034] The negative pressure adsorption in this invention uses the suction force of the negative pressure adsorption holes to press the ceramic substrate tightly against the surface of the worktable 10, preventing substrate displacement during drilling (especially considering the brittleness of the ceramic substrate, displacement can easily lead to chipping). However, this "pressing" is not absolutely gapless—micro-gaps ranging from micrometers to millimeters will remain between the ceramic substrate and the surface of the worktable 10 (naturally formed by factors such as the flatness of the worktable 10 surface and substrate thickness errors). When the negative pressure generated by the negative pressure pump 71 adsorbs and fixes the ceramic substrate, it will form a negative pressure area in the micro-gaps between the ceramic substrate and the worktable 10. The debris generated during drilling (mostly micrometer-sized ceramic particles) can "flow" from the surface of the ceramic substrate to the negative pressure adsorption holes below through this micro-gaps, and then be drawn into the pipe 73 by the negative pressure suction. At the same time, the high-pressure air nozzle 72 sprays high-pressure gas into the drilling area, which will further push the debris on the surface of the ceramic substrate towards the micro-gaps or the surrounding negative pressure adsorption holes, accelerating the entry of the debris into the debris collection box 75.

[0035] It should be noted that, to prevent the drill bit 23 from drilling into the worktable 10 during the drilling process on the ceramic substrate, a clearance hole 11 can be provided on the worktable 10 corresponding to the drilling area. This clearance hole 11 can be a blind hole or a through hole. Preferably, the surface of the worktable 10 is provided with a rubber pad 12 around the clearance hole 11 for sealing. The thickness of the rubber pad is 0.5-1mm, which does not affect the negative pressure airflow in the micro-gap between the ceramic substrate and the surface of the worktable 10, and will not cause failure to absorb debris.

[0036] In another preferred embodiment of the present invention, the worktable 10 is further provided with a plurality of positioning components 80. Each positioning component 80 includes a pressure sensor 81, a positioning block 82, and a driving component 83 for driving the positioning block 82. The driving component 83 can be an electric cylinder or a pneumatic cylinder, and its end is fixedly connected to the positioning block 82. The positioning block 82 is made of nylon, and the plurality of positioning blocks 82 are disposed at different positions on the surface of the worktable 10 for circumferential positioning of the ceramic substrate. Each positioning block 82 has a pressure sensor 81 (e.g., FSR402 type) disposed inside it to detect the clamping force of the positioning block 82 on the ceramic substrate. The surface of each pressure sensor 81 is covered with a 0.5mm thick silicone pad 12 to prevent scratching the ceramic substrate. The signal output terminal of the pressure sensor 81 is electrically connected to the control system 60. The drive assembly 83 drives the positioning block 82 to approach and contact the ceramic substrate. When the pressure sensor 81 detects that the clamping force has reached the preset value, the drive assembly 83 stops running, the positioning block 82 maintains its current position, and fixes the ceramic substrate around its perimeter. At the same time, the negative pressure pump 71 starts to adsorb and fix the bottom surface of the ceramic substrate, thus achieving double fixation of the ceramic substrate.

[0037] Example 2

[0038] This embodiment provides a control method for a ceramic substrate drilling device, based on a ceramic substrate drilling device according to Embodiment 1, including the following steps:

[0039] S1: Parameter settings. Input the Vickers hardness Hv, thickness H, target hole diameter D, and drilling depth L of the ceramic substrate. The control system automatically matches the initial processing parameters based on the input parameters, including spindle speed n, initial feed rate v0, initial ultrasonic amplitude A0, and initial ultrasonic frequency f0. (Unit: kHz), negative pressure pump suction force P0 and high pressure nozzle air pressure Q0.

[0040] S2: Substrate positioning. The ceramic substrate is placed on the worktable. The control system controls the positioning block of the positioning component to move and perform circumferential positioning of the substrate. The pressure sensor detects the clamping force. When the clamping force reaches the preset value F1=0.1×Hv×D (unit: N), the positioning block stops moving. At the same time, the negative pressure pump starts and the ceramic substrate is adsorbed and fixed through the negative pressure adsorption hole.

[0041] S3: Staged drilling process. The control system divides the machining process into three stages according to the drilling depth and dynamically adjusts the parameters.

[0042] S31: Stage 1, Inlet Section, Feed Displacement 0 < s ≤ 0.3L: Start the drive motor, the spindle rotates at speed n, the feed assembly feeds at 80% of speed v0, the ultrasonic vibration module runs at 1.2 times amplitude A0 and frequency f0, the high-pressure air nozzle sprays gas at 1.1 times air pressure Q0 to avoid inlet edge breakage, and the negative pressure pump suction P0 adsorbs waste.

[0043] S32: Stage 2, middle section, feed displacement 0.3L<s≤0.8L: feed speed increased to v0, ultrasonic amplitude adjusted to A0, frequency maintained at f0, high-pressure air nozzle pressure adjusted to Q0, negative pressure pump suction increased to 1.2 times P0, enhancing chip removal effect.

[0044] S32: Stage 3, Exit Section, Feed Displacement 0.8L<s≤L: Feed speed is reduced to 0.6 times v0, ultrasonic amplitude is adjusted to 1.1 times A0, frequency is increased to 1.1 times f0, high-pressure nozzle pressure is increased to 1.2 times Q0 to avoid outlet cracks, and negative pressure pump suction P0 adsorbs waste.

[0045] S4: Real-time adjustment. During each stage of machining, the force sensor detects the cutting force F in real time. If F > 1.2 times the initial cutting force reference value F0, the control system adjusts the ultrasonic amplitude to increase to A1, where A1 > A0, for example, by increasing the ultrasonic amplitude by 10%, while simultaneously reducing the feed rate to v1, where v1 < v0, for example, by reducing the feed rate by 15%. If F < 0.8 times the initial cutting force reference value F0, the ultrasonic amplitude is adjusted to decrease to A2, where A2 < A0, for example, by decreasing the ultrasonic amplitude by 8%, while simultaneously increasing the feed rate to v2, where v2 > v0, for example, by increasing the feed rate by 12%. The displacement sensor detects the spindle feed displacement s in real time. When the displacement reaches the drilling depth L (i.e., s = L), the control system controls the feed assembly to stop feeding, and the spindle stops rotating.

[0046] S5: Quality Inspection. A vision camera captures an image of the hole after drilling is completed. The image processor analyzes the hole wall roughness Ra, hole diameter deviation ΔD, and chipping width W. If Ra ≤ preset roughness (e.g., Ra ≤ 0.8 μm), ΔD ≤ preset hole diameter deviation (e.g., ΔD ≤ ±0.2 mm), and W ≤ preset chipping width (e.g., W ≤ 0.1 mm), the machining is deemed qualified. If it is unqualified, the control system records the unqualified parameters and prompts for adjustment of the machining parameters.

[0047] S6: Material handling, negative pressure pump shut down, positioning component released, ceramic substrate removed, drilling process completed.

[0048] In this invention, the control system incorporates a processing parameter calculation model to automatically generate initial processing parameters based on the hardness of the ceramic substrate and the drilling size, specifically including:

[0049] 1) Calculation of initial cutting force reference value:

[0050]

[0051] Where F0 is the initial cutting force reference value (unit: N), kH is the material correction factor (0.85 for alumina, 0.92 for aluminum nitride, and 1.05 for silicon carbide), D is the target hole diameter (unit: mm), and Hv is the Vickers hardness of the ceramic substrate (unit: HV).

[0052] The calculation model for the initial cutting force reference value F0 constructed in this invention is related to the material hardness Hv and the target hole diameter D. The higher the hardness and the larger the hole diameter, the larger the initial cutting force reference value, ensuring that the cutting force matches the material's shear strength and avoiding low processing efficiency due to insufficient force or substrate breakage due to excessive force.

[0053] 2) Initial feed rate calculation:

[0054]

[0055] Where v0 is the initial feed rate (unit: mm / s) and n is the spindle speed (unit: r / min).

[0056] The calculation model for the initial feed rate v0 constructed in this invention is positively correlated with the spindle speed n and the target hole diameter D, and negatively correlated with the initial cutting force reference value F0. It balances machining efficiency and cutting stability, and avoids vibration caused by high-speed feed or low efficiency caused by low-speed feed.

[0057] 3) Initial ultrasonic amplitude calculation:

[0058]

[0059] Where A0 is the initial ultrasonic amplitude (unit: μm) and L is the drilling depth (unit: mm).

[0060] The calculation model for the initial ultrasonic amplitude A0 constructed in this invention is positively correlated with hardness Hv and target hole diameter D, and negatively correlated with depth L. The higher the hardness, the larger the amplitude is needed to assist cutting, and the larger the depth, the smaller the amplitude is needed to avoid damage to the hole wall, thus achieving precise processing of holes of different sizes.

[0061] In step S3 of the present invention, when 1500HV≤Hv≤1800HV (e.g., silicon nitride, high-purity / high-density alumina), the feed displacement of the inlet section is 0<s≤0.3L, the feed displacement of the middle section is 0.3L<s≤0.8L, and the feed displacement of the outlet section is 0.8L<s≤L; when Hv>1800HV (e.g., silicon carbide), the feed displacement threshold of the inlet section is adjusted to 0.4L, and the feed displacement threshold of the outlet section is adjusted to 0.7L; when Hv<1500HV (e.g., low-purity alumina), the feed displacement threshold of the inlet section is adjusted to 0.2L, and the feed displacement threshold of the outlet section is adjusted to 0.9L.

[0062] In step S4 of the present invention, when the vision camera detects debris accumulation in the hole, the control system automatically increases the suction power of the negative pressure pump to P1, P1 > P0, for example, by 20% of the suction power of the negative pressure pump, and at the same time increases the pressure of the high-pressure nozzle to Q1, Q1 > Q0, for example, by 10% of the pressure of the high-pressure nozzle, and then returns to the initial parameters after a period of time.

[0063] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A drilling device for ceramic substrates, characterized in that, Includes a worktable, drilling mechanism, feed assembly, ultrasonic vibration module, real-time monitoring unit, and control system; The worktable is used to support and fix the ceramic substrate to be processed; The drilling mechanism includes a spindle, a drive motor, and a drill bit. The drive motor is connected to the spindle and is used to drive the spindle to rotate the drill bit. The feed assembly is used to drive the spindle to move the drill bit vertically for drilling operations; The ultrasonic vibration module is sleeved outside the main shaft, and the vibration frequency and vibration amplitude of the ultrasonic vibration module are adjustable. The real-time monitoring unit includes a vision camera, a force sensor, and a displacement sensor. The vision camera is used to capture images of the drilling area. The force sensor is located between the drilling mechanism and the feed assembly and is used to detect the cutting force during the drilling process. The displacement sensor is used to detect the feed displacement of the spindle. The control system is electrically connected to the drive motor, the feed assembly, the ultrasonic vibration module, and the real-time monitoring unit, respectively, and is used to receive monitoring data and control the operation of each component.

2. The ceramic substrate drilling device according to claim 1, characterized in that, The feed assembly includes a servo motor and a ball screw coaxially connected to the output shaft of the servo motor. The ball screw is threadedly connected to a screw sleeve fixed on the drive motor.

3. The ceramic substrate drilling device according to claim 1, characterized in that, The ultrasonic vibration module includes a vibration generator, an amplitude regulator, and a frequency controller. The vibration generator is elastically connected to the main shaft and is used to convert electrical energy into high-frequency mechanical vibration. The amplitude regulator and the frequency controller are used to adjust the ultrasonic amplitude and ultrasonic frequency, respectively.

4. The ceramic substrate drilling device according to claim 1, characterized in that, The workbench is also equipped with multiple positioning components, including a pressure sensor, a positioning block, and a driving component for moving the positioning block. The multiple positioning blocks are set at different positions on the workbench surface for circumferential positioning of the ceramic substrate. The pressure sensor is set inside the positioning block for detecting the clamping force of the positioning block on the ceramic substrate. The signal output terminal of the pressure sensor is electrically connected to the control system.

5. The ceramic substrate drilling device according to claim 1, characterized in that, It also includes a chip removal mechanism. The chip removal output control terminal of the control system is connected to the enable terminal of the chip removal mechanism. The surface of the workbench is provided with several negative pressure adsorption holes. The chip removal mechanism includes a negative pressure pump and a high-pressure air nozzle. The negative pressure pump is connected to the negative pressure adsorption holes of the workbench through a pipe. The high-pressure air nozzle is located next to the drill bit and the air outlet of the high-pressure air nozzle faces the drilling area. The high-pressure air nozzle is connected to a high-pressure air source through an air pipe. The chip removal mechanism also includes a chip collection box, which is located below the workbench and connected to the air outlet of the negative pressure pump. The chip collection box is equipped with a filter screen for filtering ceramic chips.

6. A ceramic substrate drilling device according to any one of claims 1-5, characterized in that, The control system includes a PLC controller and a touch screen. The touch screen is used to input processing parameters and display the operating status of the equipment. The PLC controller is used to adjust the feed speed of the feed assembly and the parameters of the ultrasonic vibration module in real time based on the feedback data from the force sensor and displacement sensor.

7. A control method for a ceramic substrate drilling apparatus based on any one of claims 1-6, comprising the following steps: S1: Parameter settings: Input the Vickers hardness Hv, thickness H, target hole diameter D, and drilling depth L of the ceramic substrate. The control system will automatically match the initial processing parameters based on the input parameters, including spindle speed n, initial feed speed v0, initial ultrasonic amplitude A0, initial ultrasonic frequency f0, negative pressure pump suction P0, and high-pressure nozzle air pressure Q0. S2: Substrate positioning. The ceramic substrate is placed on the worktable. The control system controls the positioning block of the positioning component to move and perform circumferential positioning of the substrate. The pressure sensor detects the clamping force. When the clamping force reaches the preset value F1=0.1×Hv×D, the positioning block stops moving. At the same time, the negative pressure pump starts and the ceramic substrate is adsorbed and fixed through the negative pressure adsorption hole. S3: Staged drilling process. The control system divides the machining process into three stages according to the drilling depth and dynamically adjusts the parameters. S31: Stage 1, Inlet Section: Start the drive motor, the spindle rotates at speed n, the feed assembly feeds at 80% of speed v0, the ultrasonic vibration module operates at 1.2 times amplitude A0 and frequency f0, the high-pressure air nozzle sprays gas at 1.1 times air pressure Q0 to avoid inlet edge breakage, and the negative pressure pump suction P0 adsorbs waste debris; S32: Phase Two, Mid-Stage: Feed speed increased to v0, ultrasonic amplitude adjusted to A0, frequency maintained at f0, high-pressure nozzle pressure adjusted to Q0, negative pressure pump suction increased to 1.2 times P0, enhancing chip removal effect; S32: Stage 3, Outlet Section: Feed speed is reduced to 0.6 times v0, ultrasonic amplitude is adjusted to 1.1 times A0, frequency is increased to 1.1 times f0, high-pressure nozzle pressure is increased to 1.2 times Q0 to avoid outlet cracks, and negative pressure pump suction P0 adsorbs waste. S4: Real-time adjustment. During each stage of machining, the force sensor detects the cutting force F in real time. If F > 1.2 times the initial cutting force reference value F0, the control system adjusts the ultrasonic amplitude to increase to A1, where A1 > A0, and simultaneously reduces the feed speed to v1, where v1 < v0. If F < 0.8 times the initial cutting force reference value F0, the ultrasonic amplitude is adjusted to decrease to A2, where A2 < A0, and simultaneously the feed speed is increased to v2, where v2 > v0. The displacement sensor detects the spindle feed displacement s in real time. When the displacement reaches the drilling depth L, the control system controls the feed assembly to stop feeding, and the spindle stops rotating. S5: Quality inspection. The vision camera captures images of the hole after drilling is completed. The image processor analyzes the hole wall roughness Ra, hole diameter deviation ΔD, and chipping edge width W. If Ra ≤ preset roughness, ΔD ≤ preset hole diameter deviation, and W ≤ preset chipping edge width, the processing is deemed qualified. If it is unqualified, the control system records the unqualified parameters and prompts for adjustment of the processing parameters. S6: Material handling, negative pressure pump shut down, positioning component released, ceramic substrate removed, drilling process completed.

8. The control method according to claim 7, characterized in that, The control system has a built-in processing parameter calculation model, which is used to automatically generate initial processing parameters based on the hardness of the ceramic substrate and the drilling size, specifically including: 1) Calculation of initial cutting force reference value: Where F0 is the initial cutting force reference value (unit: N), kH is the material correction factor (0.85 for alumina, 0.92 for aluminum nitride, and 1.05 for silicon carbide), D is the target hole diameter (unit: mm), and Hv is the Vickers hardness of the ceramic substrate (unit: HV). 2) Initial feed rate calculation: Where v0 is the initial feed rate (unit: mm / s) and n is the spindle speed (unit: r / min). 3) Initial ultrasonic amplitude calculation: Where A0 is the initial ultrasonic amplitude (unit: μm) and L is the drilling depth (unit: mm).

9. The control method according to claim 7, characterized in that, In step S3, When 1500HV≤Hv≤1800HV (such as silicon nitride, high purity / high density alumina), the feed displacement of the inlet section is 0<s≤0.3L, the feed displacement of the middle section is 0.3L<s≤0.8L, and the feed displacement of the outlet section is 0.8L<s≤L. When Hv > 1800HV (e.g., silicon carbide), the inlet section feed displacement threshold is adjusted to 0.4L, and the outlet section feed displacement threshold is adjusted to 0.7L. When Hv < 1500HV (such as low-purity alumina), the inlet section feed displacement threshold is adjusted to 0.2L, and the outlet section feed displacement threshold is adjusted to 0.9L.

10. The control method according to claim 7, characterized in that, In step S4, when the vision camera detects debris accumulating in the hole, the control system automatically increases the suction of the negative pressure pump to P1, where P1 > P0, and at the same time increases the air pressure of the high-pressure nozzle to Q1, where Q1 > Q0. After a period of time, the system returns to the initial parameters.

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