A multi-band laser confocal processing equipment and processing method for silicon carbide ingots

Abstract

A multi-band laser confocal processing equipment and method for silicon carbide ingots, comprising a stage and a laser assembly. The laser assembly includes a first laser, a second laser, a first reflector, a second reflector, and a laser focusing lens. After the first reflector reflects the first-wavelength laser emitted by the first laser, it outputs with the second-wavelength laser emitted by the second laser reflected by the second reflector in a common optical path, and the laser focusing lens processes the ingot to be processed on the stage. The stage includes an X-axis movement module, a Y-axis movement module, a C-axis module, and a B-axis module. The C-axis module is used to drive the ingot to be processed to rotate around its vertical central axis, and the B-axis module is used to drive the ingot to be processed to swing in the vertical plane. The present invention can improve the laser processing efficiency, can cut out cylindrical ingots, has a simple structure, is easy to operate and control, and has a low cost, and is especially suitable for cutting silicon carbide ingots with large thickness, high hardness, and high precision.

Description

Technical Field

[0001] The present invention relates to the technical field of laser processing, and particularly to a multi-band laser confocal silicon carbide ingot processing device and a processing method thereof. Background Art

[0002] Laser processing utilizes the energy of light to reach a very high energy density at the focus after being focused by a lens, and processes by means of the photothermal effect. By using the high energy and high focusing properties of the laser beam, operations such as cutting, engraving, welding, drilling, surface modification, and grinding of materials are realized through processing methods such as heating, melting, evaporation, and combustion of the workpiece surface. It has the advantages of fast processing speed, small surface deformation, and the ability to process various materials, so it is widely used in various industrial manufacturing fields.

[0003] With the development of laser processing technology, the method of only using single-wavelength laser to process workpieces is difficult to meet the increasingly strict requirements for the processing efficiency and quality of workpieces. Instead, it is more inclined to use dual-wavelength or multi-band lasers to process workpieces. However, the existing dual-wavelength or multi-band laser processing technology is still immature and there are still some problems that are not conducive to meeting complex processing requirements.

[0004] Meanwhile, in the existing laser processing technology, in conventional laser processing, since the conventional laser beam is a conical laser beam 14, it is difficult to achieve taper-free cutting. As Figure 1 shown, it results in the inner wall 82 or the cut edge processed by the laser not being perpendicular, forming an inclined surface, and it is difficult to obtain a cylindrical shape with the side surface and the bottom surface being completely perpendicular, forming a frustum. Although the laser micro water jet technology can be used to solve this problem and obtain high-quality processed walls and cut edges, its equipment cost is high, and the high-power density laser in the water beam will cause a large amount of loss of laser energy due to continuous reflection and absorption, resulting in its limitation in high-power applications and slower cutting speed; during the processing, due to the high energy density of the laser and the rapid heating and cooling process, microcracks may be generated inside the material, affecting the quality and strength of the processed parts, especially for precision workpieces such as semiconductor silicon wafers, directly affecting the finished product quality; and currently, the water-guided laser processing technology is limited by aspects such as the stability of the water beam, the effective length, and the control of the laser spot size, resulting in its cutting accuracy being difficult to further improve and its adaptability under different material and thickness conditions being poor. Therefore, for the processing of silicon carbide ingots, new solutions need to be sought. Summary of the Invention

[0005] The object of the present invention is to overcome the above-mentioned disadvantages of the prior art, and provide a multi-band laser confocal silicon carbide ingot processing device with high laser energy, high processing efficiency, good processing quality, simple structure, easy operation and control, and low cost, as well as a multi-band laser confocal silicon carbide ingot processing method, which is particularly suitable for the processing of silicon carbide ingots with large thickness, high hardness, high precision, and high price.

[0006] The present invention is realized by the following technical solutions:

[0007] A multi-band laser confocal silicon carbide ingot processing device, including a stage and a laser assembly. The stage is used to carry the ingot to be processed. The laser assembly includes a first laser, a second laser, a first reflector, a second reflector and a laser focusing lens. The first reflector is used to reflect the first-wavelength laser emitted by the first laser, and the second reflector is used to reflect the second-wavelength laser emitted by the second laser. The reflected first-wavelength laser and the reflected second-wavelength laser are output in a common optical path, and the laser focusing lens is used to process the ingot to be processed on the stage. The stage includes an X-axis movement module, a Y-axis movement module, a C-axis module and a B-axis module. The Y-axis movement module is arranged on the X-axis movement module, the B-axis module is arranged on the Y-axis movement module, the C-axis module is arranged on the B-axis module, and the C-axis module is connected to the ingot to be processed. The C-axis module is used to drive the ingot to be processed to rotate around its vertical central axis, and the B-axis module is used to drive the ingot to be processed to swing in the vertical plane, so that the vertical central axis of the ingot to be processed is inclined relative to the vertical direction (Z-axis direction), so as to eliminate the cutting influence of the conical laser beam focused by the laser focusing lens on the side of the ingot, and thus process a cylindrical ingot with a side surface completely perpendicular to the bottom surface.

[0008] Furthermore, the laser assembly further includes a laser cutting head and a first Z-axis movement module. The laser focusing lens is arranged in the laser cutting head. The output end of the laser cutting head faces the ingot to be processed. The laser cutting head is installed on the first Z-axis movement module and moves up and down in the vertical direction through the first Z-axis movement module. The parallel laser beam emitted by the first laser or the second laser is focused by the laser focusing lens on the laser cutting head, and the laser focus is focused on the ingot to be processed by the up and down movement of the first Z-axis movement module.

[0009] Furthermore, the first reflector and the second reflector are arranged parallel to each other up and down. The first reflector is located above the second reflector. The first reflector is a total reflection mirror, and the second reflector is a coated semi-transparent and semi-reflective mirror, which can allow the first-wavelength laser to pass through while reflecting the second-wavelength laser. The first-wavelength laser emitted by the first laser is reflected by the first reflector and then passes through the second reflector, and is output in a common optical path with the second-wavelength laser reflected by the second reflector emitted by the second laser, and converges on the laser focusing lens.

[0010] Further, the B-axis module is used to drive the ingot to be processed to swing in the vertical plane, so that the vertical central axis of the ingot to be processed deflects an angle α relative to the vertical direction (Z-axis direction), where α = θ / 2, and θ is the cone angle of the conical laser beam. D is the beam diameter incident on the laser focusing lens, and W D is the distance between the laser focusing lens and the laser focus, which can also be replaced by the focal length.

[0011] Further, it also includes a positioning area. Above the positioning area, there are several concentric annular positioning lights for projecting several positioning rings for positioning the stage and the ingot to be processed in the positioning area. The stage includes a processing seat and a circular vacuum chuck. The processing seat is installed on the C-axis module, and the C-axis module drives the processing seat to rotate around its rotation axis. The vacuum chuck is arranged on the processing seat, and the vacuum chuck is connected with a vacuum generating device for fixing the ingot to be processed in the form of vacuum adsorption. The center of the vacuum chuck is located on the rotation axis of the processing seat. The processing seat positions the centers of the vacuum chuck and the ingot to be processed at the centers of the corresponding positioning rings respectively under the drive of the X-axis movement module and the Y-axis movement module for positioning.

[0012] Further, support columns are arranged on the positioning area, and a second Z-axis movement module is arranged on the support columns. Several of the annular positioning lights are installed on the second Z-axis movement module, and the second Z-axis movement module drives the annular positioning lights to move up and down along the support columns to project positioning rings with the same center but different diameters to adapt to the processing of ingots with different diameters.

[0013] Further, the B-axis module includes a swing motor, a swing plate and a swing arm. One end of the swing plate is perpendicularly connected to the output shaft of the swing motor, and the other end is perpendicularly connected to the swing arm; the C-axis module includes a rotation motor and a processing seat. The rotation motor is installed on the swing arm, the processing seat is drivingly connected to the rotation motor, and the rotation axis of the processing seat is perpendicular to the rotation axis of the swing motor.

[0014] A multi-band laser confocal silicon carbide ingot processing method uses the above multi-band laser confocal silicon carbide ingot processing equipment, and includes the following steps:

[0015] S1. Perform parameter settings on the control system. The set parameters include the diameter and thickness of the final ingot product, the parameters of the V-shaped cutting groove, the laser parameters and the rotation speed n of the C-axis module. The control system calculates the deflection angle α of the B-axis module according to the set parameters, automatically plans the laser cutting path for layer-by-layer processing, and calculates the processing time.

[0016] The parameters of the V-shaped cutting groove include the maximum width L of the V-shaped cutting groove, the included angle β between the two sides of the V-shaped cutting groove, and the laser depth step H. The laser depth step H is the distance between two adjacent upper and lower layers during layer-by-layer processing. The laser parameters include laser power, laser frequency, pulse width, and duty cycle; the deflection angle α = θ / 2, where θ is the cone angle of the conical laser beam. D is the beam diameter incident on the laser focusing lens, and W D is the distance between the laser focusing lens and the laser focus, and can also be replaced by the focal length of the laser focusing lens;

[0017] S2. Move and position the ingot to be processed to the processing area through the X-axis movement module and the Y-axis movement module. Then, control the B-axis module according to the deflection angle α to swing the ingot to be processed in the vertical direction so that the included angle between its vertical central axis and the vertical direction is α. Then, focus the laser generated by the laser component on the surface of the ingot to be processed through the CCD autofocus system, and cut the side surface of the ingot according to the planned laser cutting path.

[0018] S3. After the side surface of the ingot is cut, the control system controls the B-axis module to swing the ingot in the vertical direction so that its vertical central axis returns to the vertical direction, focus the laser on the surface of the ingot to be processed, and cooperate with the movements of the X-axis movement module, the Y-axis movement module, and the C-axis module to process the top surface or the bottom surface of the ingot according to the planned laser processing path.

[0019] Further, in the laser cutting path of the layer-by-layer processing in step S1, the width of each layer gradually narrows from top to bottom, and finally forms the V-shaped cutting groove in the vertical section. The included angle β between the two sides of the V-shaped cutting groove is β = θ, where θ is the cone angle of the conical laser beam. where D is the beam diameter incident on the laser focusing lens, and W D is the distance between the laser focusing lens and the laser focus; during the processing of each layer, a path of processing ring by ring from the inside to the outside or from the outside to the inside is adopted.

[0020] The parameters of the laser cutting path include the processing width L of each layer n , the laser width step M, and the laser moving speed V. The processing width L of each layer is the processing width of each layer during layer-by-layer processing. The laser width step M is the step between two adjacent rings during the ring-by-ring processing of the laser on each layer. The laser moving speed V is the linear speed of the laser during the ring-by-ring processing, V = πr·n / 30, mm / s, where r is the rotation radius at the cutting point, mm; π is the constant 3.14, dimensionless; n is the rotation speed of the C-axis rotation, revolutions / min.

[0021] Further, the method of moving and positioning the ingot to be processed to the processing area by the X-axis moving module and the Y-axis moving module in step S2 is as follows: A number of concentric ring-shaped positioning lights that can be lifted and moved are arranged above the positioning area. The carrier table includes a processing seat and a circular vacuum chuck. The processing seat is installed on the C-axis module, and the vacuum chuck is arranged on the processing seat and is used to fix the ingot to be processed in the form of vacuum adsorption. The center of the vacuum chuck is located on the rotating shaft of the processing seat. Adjust the height of the ring-shaped positioning lights according to the size of the ingot to be processed, project positioning rings corresponding to the vacuum chuck and the ingot size respectively in the positioning area. First, control the X-axis moving module and the Y-axis moving module to move the vacuum chuck to the corresponding positioning ring, so that the center of the vacuum chuck coincides with the center of gravity of the positioning ring corresponding to the chuck. Then, place the ingot to be processed on the vacuum chuck, so that the center of the ingot to be processed coincides with the center of the positioning ring corresponding to the ingot. Then, fix the ingot to be processed by vacuum adsorption, and then control the Y-axis moving module to move the ingot to be processed to the processing area under the laser component.

[0022] By setting the first laser, the second laser, the first reflector, the second reflector and the laser focusing mirror, the present invention realizes the coupling of dual-band lasers, can integrate the advantages of two bands or even more bands of lasers, improve the intensity of laser output, and improve the laser processing efficiency. It is especially suitable for laser cutting of materials such as silicon carbide ingots with large thickness and high hardness. By setting the B-axis module on the basis of a conventional processing platform, driving the processing platform to swing in the vertical direction, so that the ingot to be processed is placed obliquely, and its central axis is parallel to the side of the conical laser beam, so that the side of the cut ingot is parallel to the central axis and perpendicular to the bottom surface of the ingot, obtaining a cylindrical ingot, overcoming the defect that the side cut by the conical edge of the conical laser beam is inclined during conventional laser cutting of the side. Compared with the problems of high equipment cost, large laser energy loss, slow cutting speed, easy generation of microcracks inside precision materials, poor stability and difficult control in the water-guided laser technology, this solution has many advantages such as simple structure, easy operation and control, and low cost, and is especially suitable for cutting silicon carbide ingots with large thickness, high hardness and high precision. For silicon carbide ingot materials, the side of the ingot is cut by a layered step-by-step processing method, and the width gradually becomes narrower from top to bottom, and finally a V-shaped processing groove is formed on the vertical section, which can save the material to be cut and removed to the greatest extent, and also improve the processing efficiency, and is suitable for the processing of silicon carbide ingots with high price, large thickness and high hardness. For each layer, a ring-by-ring processing method is adopted, and in cooperation with the C-axis module moving inwards or outwards ring by ring, it is easy to perform automatic control. By setting the ring-shaped positioning lights that can be lifted and moved, positioning rings of different diameters can be obtained, and in cooperation with the X-axis moving module and the Y-axis moving module, the positioning and coaxial processing of the workpiece can be realized, further improving the efficiency and accuracy of laser processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the schematic diagram of the prior art in the background art of the present invention.

[0024] Figure 2 This is the structural schematic diagram of the embodiment of the present invention.

[0025] Figure 3 This is the optical path schematic diagram of the embodiment of the present invention.

[0026] Figure 4 This is the enlarged partial structure diagram of the embodiment of the present invention.

[0027] Figure 5 This is the structural schematic diagram of the C-axis module and the B-axis module in the embodiment of the present invention.

[0028] Figure 6 This is the side view schematic diagram of the C-axis module and the B-axis module in the embodiment of the present invention.

[0029] Figure 7 This is the schematic diagram of the conical laser beam and the structure on the workpiece in the embodiment of the present invention.

[0030] Figure 8 This is the machining schematic diagram of the conical laser beam on the workpiece in the embodiment of the present invention.

[0031] Figure 9 This is the installation position schematic diagram of the annular positioning lamp in the embodiment of the present invention.

[0032] Figure 10 This is the schematic diagram of workpiece positioning in the embodiment of the present invention.

[0033] Figure 11 This is the schematic diagram of the positioning ring in the embodiment of the present invention.

[0034] Figure 12 This is the path schematic diagram of the side cutting of the ingot in the embodiment of the present invention. <�

[0035] Figure 13 This is the path schematic diagram in the depth direction during the side cutting of the ingot in the embodiment of the present invention.

[0036] Figure 14 This is the path schematic diagram in the width direction during the side cutting of the ingot in the embodiment of the present invention.

[0037] Figure 15 This is the working flowchart of the processing method in the embodiment of the present invention.

[0038] Reference numerals: 1 - first laser; 2 - second laser; 3 - first reflector; 4 - second reflector; 5 - laser focusing lens; 6 - laser cutting head; 7 - first Z-axis moving module; 8 - ingot 8; 9 - processing seat; 10 - rotating motor; 11 - B-axis module; 12 - X-axis moving module; 13 - Y-axis moving module; 14 - conical laser beam; 15 - annular positioning lamp; 16 - support column; 17 - second Z-axis moving module; 18 - positioning ring; 19 - vacuum chuck; 111 - swing motor; 112 - swing plate; 113 - swing arm; 81 - vertical central axis; 82 - side; 83 - V-shaped cutting groove. Detailed implementation manners

[0039] A multi-band laser confocal silicon carbide ingot processing device, as Figure 2 shown, comprising a stage and a laser assembly. The stage is used for carrying the ingot 8 to be processed, and the laser assembly includes a first laser 1, a second laser 2, a first reflector 3, a second reflector 4, a laser cutting head 6, a laser focusing lens 5 and a first Z-axis moving module 7. The first laser 1 emits laser of a first wavelength, and the first reflector 3 is used for reflecting the laser of the first wavelength emitted by the first laser 1. The second reflector 4 is used for reflecting the laser of a second wavelength emitted by the second laser 2. The reflected laser of the first wavelength and the reflected laser of the second wavelength are output in a common optical path, and the laser focusing lens 5 is used for processing the ingot 8 to be processed on the stage.

[0040] The laser focusing lens 5 is arranged in the laser cutting head 6. The output end of the laser cutting head 6 faces the ingot 8 to be processed. The laser cutting head 6 is mounted on the first Z-axis moving module 7 and moves up and down in the vertical direction through the first Z-axis moving module 7 to adjust the distance between the laser cutting head 6 and the ingot 8 to be processed on the stage, so as to facilitate focal point focusing and realize precise control of the processing depth of the ingot 8. The parallel laser beam emitted by the first laser 1 or the second laser 2 is focused by the laser focusing lens 5 on the laser cutting head 6, and the up and down movement of the first Z-axis moving module 7 makes the laser focal point on the ingot 8 to be processed.

[0041] The stage includes an X-axis moving module 12, a Y-axis moving module 13, a C-axis module and a B-axis module 11. The Y-axis moving module 13 is arranged on the X-axis moving module 12. The B-axis module 11 is arranged on the Y-axis moving module 13. The C-axis module is arranged on the B-axis module 11. The C-axis module is connected to the ingot 8 to be processed. The C-axis module is used for driving the ingot 8 to be processed to perform a rotary motion around its vertical central axis 81, as Figures 6 to 8, the B-axis module 11 is used to drive the ingot 8 to be processed to swing in a vertical plane, so that the vertical central axis 81 of the ingot 8 to be processed is inclined relative to the vertical direction (Z-axis direction), so as to eliminate the cutting effect of the conical laser beam 14 focused by the laser focusing mirror 5 on the side surface 82 of the ingot 8, thereby machining a cylindrical ingot 8 with a side surface 82 that is completely perpendicular to the bottom surface.

[0042] As one of the implementation manners, such as Figures 4 to 6 , the B-axis module 11 includes a swing motor 111, a swing plate 112 and a swing arm 113. One end of the swing plate 112 is vertically connected to the output shaft of the swing motor 111, and the other end is vertically connected to the swing arm 113; the C-axis module includes a rotation motor 10 and a processing seat 9. The rotation motor 10 is installed on the swing arm 113, and the processing seat 9 is drivingly connected to the rotation motor 10, and the rotation axis of the processing seat 9 is perpendicular to the rotation axis of the swing motor 111. The rotation motor 10 and the processing seat 9 can be arranged on the swing arm 113, and the output shaft of the rotation motor 10 is parallel (such as Figure 5 ) or perpendicular (such as Figure 4 ) to the rotation axis of the processing seat 9, and the output shaft of the rotation motor 10 and the rotation axis of the processing seat 9 can be connected by gear transmission. The swing motor 111 drives the swing plate 112 to rotate in a vertical plane, thereby driving the swing arm 113 and the C-axis module to swing in the vertical direction, and the rotation motor 10 drives the processing seat 9 and the ingot 8 to be processed thereon to rotate around the central axis of the processing seat 9.

[0043] The mutual cooperation of the X-axis movement module 12, the Y-axis movement module 13 and the first Z-axis movement module 7 can realize the accurate positioning of the ingot 8 to be processed and the accurate focusing of the laser focus on the ingot 8. The C-axis module rotates the ingot 8, which can cooperate with the laser to cut the side surface 82 of the ingot 8. The B-axis module 11 inclines the ingot 8 during processing, and the central axis of the ingot 8 is inclined at an angle relative to the vertical direction, which can eliminate the phenomenon that the side surface 82 of the ingot 8 processed by the conical laser beam 14 has a certain taper and cannot be completely perpendicular to the bottom surface, and the ingot 8 presents a conical shape with a smaller top and a larger bottom (such as Figure 1 ). Specifically, such as Figure 7 , Figure 8 , set the B-axis module 11 to drive the ingot 8 to be processed to swing in a vertical plane, so that the vertical central axis 81 of the ingot 8 to be processed deflects an angle α relative to the vertical direction (Z-axis direction), α = θ / 2, where θ is the cone angle of the conical laser beam 14, and θ can be calculated by , then D is the beam diameter incident on the laser focusing mirror 5, W Dis the distance between the laser focusing lens 5 and the laser focus, and can also be replaced by the focal length. In this way, the vertical central axis 81 of the ingot 8 is parallel to the side of the conical laser beam 14 close to the ingot 8. When the ingot 8 rotates around its vertical central axis 81, the area swept by the side of the conical laser beam 14 on the ingot 8 forms the side 82 of the ingot 8. The side 82 of the ingot 8 can be parallel to its vertical central axis 81, and the vertical central axis 81 of the ingot 8 is perpendicular to its bottom surface. In this way, the side 82 of the ingot 8 can be made completely perpendicular to the bottom surface.

[0044] In this embodiment, the coupling structure of the dual-band laser is specifically as follows. Figure 3 , the first reflector 3 and the second reflector 4 are arranged parallel to each other up and down and are both inclined at 45 degrees. The first laser 1 and the second laser 2 both emit laser beams in the horizontal direction. The first reflector 3 is located above the second reflector 4. The first reflector 3 is a total reflector, and the second reflector 4 is a coated semi-transparent and semi-reflective mirror, which can reflect the second-wavelength laser and allow the first-wavelength laser to pass through at the same time. Specifically, with reference to the prior art, a first-wavelength laser anti-reflection film is deposited on the surface of the second reflector 4 facing the first reflector 3. If the first-wavelength laser is infrared light, it is an infrared anti-reflection film. A second-wavelength laser high-reflection film is deposited on the surface of the second reflector 4 facing the second laser 2. If the second-wavelength laser is blue light, it is a blue light high-reflection film. The first-wavelength laser in the horizontal direction emitted by the first laser 1 is reflected by the first reflector 3 and then vertically downward, and then passes through the second reflector 4. After converging with the second-wavelength laser in the horizontal direction emitted by the second laser 2 and reflected by the second reflector 4 and vertically downward, they are output in a common optical path, converge on the laser focusing lens 5, and then vertically downward focus on the ingot 8. The laser beam obtained in this way can combine the processing advantages of the two wavelengths, enhance the intensity of the laser output, further improve the efficiency and quality of laser processing, meet various quality requirements of laser processing, and is especially suitable for laser processing of materials such as silicon carbide ingot 8 with large thickness and high hardness.

[0045] The first-wavelength laser and the second-wavelength laser can be set according to actual needs. For example, the first-wavelength laser can be infrared light, and the first laser 1 corresponds to an infrared fiber laser. The second-wavelength laser can be green light, and the second laser 2 corresponds to a green light laser. According to the actual situation, more lasers of other wavelengths can also be coupled in the same way, such as blue light, to output a multi-band composite laser. The lasers of each wavelength are independently set, and the parameters of each wavelength laser can be independently adjusted to meet various processing requirements.

[0046] The first reflector 3 and the second reflector 4 are set to be detachably connected, which is convenient for the installation and replacement of the first reflector 3 and the second reflector 4. The first laser 1 and the second laser 2 can also be set to be detachably connected, which is convenient for the installation and replacement of the first laser 1 and the second laser 2.

[0047] To accurately position the ingot 8 to be processed in the processing area under the laser assembly, such as Figure 9 , Figure 10 , the present invention further provides a positioning area, which is located in the area covered by the X-axis moving module 12 and the Y-axis moving module 13. Above the positioning area, a number of concentric annular positioning lights 15 are provided, which are used to project a number of positioning rings 18 for positioning the carrier table and the ingot 8 to be processed in the positioning area. The carrier table includes a processing seat 9 and a circular vacuum chuck 19. The processing seat 9 is installed on the C-axis module, and the C-axis module drives the processing seat 9 to rotate around its rotating shaft. The vacuum chuck 19 is arranged on the processing seat 9. The vacuum chuck 19 is connected to a vacuum generating device and is used to fix the ingot 8 to be processed in the form of vacuum adsorption. And the center of the vacuum chuck 19 is located on the rotating shaft of the processing seat 9. The processing seat 9 positions the centers of the vacuum chuck 19 and the ingot 8 to be processed to the centers of the corresponding positioning rings 18 respectively under the drive of the X-axis moving module 12 and the Y-axis moving module 13 for positioning, which can ensure the accurate positioning of the processed workpiece, keep it coaxial with the rotating shaft of the processing seat 9, realize coaxial processing, and improve the processing accuracy.

[0048] To adapt to the processing of ingots 8 of different sizes, including non-standard sizes, support columns 16 are provided on the positioning area. A second Z-axis moving module 17 is provided on the support columns 16. A number of the annular positioning lights 15 are installed on the second Z-axis moving module 17. The second Z-axis moving module 17 drives the annular positioning lights 15 to move up and down along the support columns 16, such as Figure 11 , and positioning rings 18 with the same center but different diameters can be projected, corresponding to the sizes of 4, 6, 8, 10, and 12-inch conventional ingots 8, and can also be changed arbitrarily according to the size of the ingot 8. The second Z-axis moving module 17 can be in a manual moving mode. As Figure 9 shown, the height of the annular positioning light 15 can be manually adjusted by rotating the handwheel.

[0049] A multi-band laser confocal silicon carbide ingot processing method uses the above-mentioned multi-band laser confocal silicon carbide ingot processing equipment, such as Figure 15 , and includes the following steps:

[0050] S1. Set parameters on the control system. The set parameters include the diameter and thickness of the final ingot product, the parameters of the V-shaped cutting groove, the laser parameters, and the rotation speed n of the C-axis module. The control system calculates the deflection angle α of the B-axis module 11 according to the set parameters, automatically plans the laser cutting path for layer-by-layer processing (such as Figure 12 ), and calculates the processing time.

[0051] Such as Figure 13, the parameters of the V-shaped cutting groove include the maximum width L of the V-shaped cutting groove, the included angle β between the two sides of the V-shaped cutting groove, and the laser depth step H. The laser depth step H is the distance between two adjacent upper and lower layers during layer-by-layer processing. The laser parameters include laser power, laser frequency, pulse width, and duty cycle; as Figure 7 , Figure 8 , the deflection angle α = θ / 2, where θ is the cone angle of the conical laser beam, D is the beam diameter incident on the laser focusing lens, W D is the distance between the laser focusing lens and the laser focus, and can also be replaced by the focal length of the laser focusing lens.

[0052] As one of the implementation manners, in the laser cutting path of layer-by-layer processing, as Figure 13 , the width of each layer gradually narrows from top to bottom, and the V-shaped cutting groove is finally formed in the vertical section. To make the width of the V-shaped cutting groove 83 as narrow as possible and remove as little material as possible during cutting to improve the raw material utilization rate, the included angle β between the two sides of the V-shaped cutting groove 83 = θ, where θ is the cone angle of the conical laser beam 14, where, D is the beam diameter incident on the laser focusing lens, W D is the distance between the laser focusing lens and the laser focus; during the processing of each layer, as Figure 14 , a path of processing ring by ring from the inside to the outside or from the outside to the inside is adopted.

[0053] The parameters of the laser cutting path include the processing width L of each layer n , the laser width step M, and the laser moving speed V. The processing width L of each layer is the processing width of each layer during layer-by-layer processing. The laser width step M is the step between two adjacent rings during the ring-by-ring processing of the laser on each layer. The laser moving speed V is the linear speed of the laser during the ring-by-ring processing, V = πr·n / 30, mm / s, where r is the turning radius at the cutting point, mm; π is the constant 3.14, dimensionless; n is the rotational speed of the C-axis rotation, revolutions per minute.

[0054] S2. Move and position the ingot to be processed to the processing area through the X-axis movement module and the Y-axis movement module, and then control the B-axis module according to the deflection angle α to swing the ingot to be processed in the vertical direction so that the included angle between its vertical central axis and the vertical direction is α; then focus the laser generated by the laser component on the surface of the ingot to be processed through the CCD autofocus system, and perform cutting according to the planned laser cutting path, including the rotation of the C-axis module, the movement of the X-axis movement module 12, the Y-axis movement module 13, and the first Z-axis movement module 7. By placing the ingot 8 to be processed obliquely so that its inclination is adapted to the inclination of the conical side of the conical laser beam 14, a cylinder without taper is cut on the ingot 8, thereby realizing taper-free processing.

[0055] Specifically, the positioning method of the ingot 8 to be processed can be as follows: Figure 10 A number of concentric ring-shaped positioning lights 15 that can be lifted and moved are arranged above the positioning area. The stage includes a processing seat 9 and a circular vacuum chuck 19. The processing seat 9 is installed on the C-axis module. The vacuum chuck 19 is arranged on the processing seat 9 and is used to fix the ingot 8 to be processed in the form of vacuum adsorption. The center of the vacuum chuck 19 is located on the rotating shaft of the processing seat 9, and the vacuum chuck 19 rotates coaxially with the processing seat 9. Adjust the height of the ring-shaped positioning lights 15 according to the size of the ingot 8 to be processed, and project concentric positioning rings 18 corresponding to the vacuum chuck 19 and the size of the ingot 8 in the positioning area. First, control the X-axis movement module 12 and the Y-axis movement module 13 to move the vacuum chuck 19 to the corresponding positioning ring 18, so that the center of the vacuum chuck 19 coincides with the center of gravity of the positioning ring 18 corresponding to the vacuum chuck 19 (it is sufficient that the edge of the vacuum chuck 19 coincides with the edge of the corresponding positioning ring 18), and then place the ingot 8 to be processed on the vacuum chuck 19, so that the center of the ingot 8 to be processed coincides with the center of the positioning ring 18 corresponding to the ingot, and then fix the ingot 8 to be processed by vacuum adsorption, and then control the Y-axis movement module 13 to move the ingot 8 to be processed to the processing area under the laser assembly. This can ensure the accurate positioning of the ingot and also ensure that the ingot is coaxial with the rotating shaft of the processing seat, realize coaxial processing, and ensure the accuracy of processing.

[0056] After the side cutting of the ingot is completed, the control system controls the B-axis module to swing the ingot in the vertical direction, so that its vertical central axis returns to the vertical direction, focuses the laser on the surface of the ingot to be processed, and cooperates with the movements of the X-axis movement module, the Y-axis movement module, and the C-axis module to process the top or bottom surface of the ingot according to the planned laser processing path. The processing of the surface (top or bottom surface) of the ingot 8 can adopt conventional methods, such as in a circular outward or inward manner, to grind and polish the surface of the ingot 8.

[0057] The whole process of laser cutting and laser processing is controlled by a control system (industrial computer), including: controlling the movements of the X-axis movement module 12 and the Y-axis movement module 13 to position and cooperate with the movement of the ingot 8 to be processed; controlling the movement of the first Z-axis movement module 7 to adjust the focus position of the laser, realizing focusing and stepping in the processing depth direction; controlling the CCD autofocus system to automatically capture the processing area information through vision technology to facilitate focusing; controlling the movement of the C-axis module to make the ingot 8 to be processed rotate; controlling the movement of the B-axis module 11 to tilt or straighten the ingot 8, which is mainly used to cut out a cylindrical ingot 8 with a vertical side 82; planning the cutting path of the side 82 of the ingot 8 and the processing path of the surface of the ingot 8, including various processing parameters.

[0058] The above detailed description is a specific description of the feasible embodiments of the present invention. Such embodiments are not intended to limit the patent scope of the present invention. Any equivalent implementation or modification without departing from the present invention shall be included in the patent scope of this case.

Claims

1. A multi-band laser confocal silicon carbide ingot processing device, characterized in that, It includes a stage and a laser assembly. The stage is used to carry the ingot to be processed. The laser assembly includes a first laser, a second laser, a first reflector, a second reflector, and a laser focusing lens. The first reflector is used to reflect the first-wavelength laser emitted by the first laser, and the second reflector is used to reflect the second-wavelength laser emitted by the second laser. The reflected first-wavelength laser and the reflected second-wavelength laser are output in a common optical path and the ingot to be processed on the stage is processed through the laser focusing lens. The stage includes an X-axis movement module, a Y-axis movement module, a C-axis module, and a B-axis module. The Y-axis movement module is arranged on the X-axis movement module, the B-axis module is arranged on the Y-axis movement module, the C-axis module is arranged on the B-axis module, and the C-axis module is connected to the ingot to be processed. The C-axis module is used to drive the ingot to be processed to rotate around its vertical central axis, and the B-axis module is used to drive the ingot to be processed to swing in a vertical plane, so that the vertical central axis of the ingot to be processed is inclined relative to the vertical direction to eliminate the cutting influence of the conical laser beam focused by the laser focusing lens on the side of the ingot, thereby processing a cylindrical ingot with a side surface perpendicular to the bottom surface completely. The B-axis module is used to drive the ingot to be processed to swing in the vertical plane, so that the vertical central axis of the ingot to be processed deflects an angle α relative to the vertical direction, where α = θ / 2, and θ is the cone angle of the conical laser beam. , D is the beam diameter incident on the laser focusing mirror, and W D is the distance between the laser focusing mirror and the laser focus.

2. The multi-band laser confocal silicon carbide ingot processing equipment according to claim 1, characterized in that, The laser assembly further includes a laser cutting head and a first Z-axis movement module. The laser focusing lens is arranged in the laser cutting head. The output end of the laser cutting head faces the ingot to be processed. The laser cutting head is installed on the first Z-axis movement module and moves up and down in the vertical direction through the first Z-axis movement module. The parallel laser beam emitted by the first laser or the second laser is focused by the laser focusing lens on the laser cutting head, and the laser focus is focused on the ingot to be processed by the up and down movement of the first Z-axis movement module.

3. A multi-band laser confocal silicon carbide ingot processing device according to claim 1, wherein, The first reflector and the second reflector are arranged parallel to each other vertically. The first reflector is located above the second reflector. The first reflector is a total reflector, and the second reflector is a coated semi-transparent and semi-reflective mirror, which can allow the first-wavelength laser to pass through while reflecting the second-wavelength laser. The first-wavelength laser emitted by the first laser is reflected by the first reflector and then passes through the second reflector, and is output in a common optical path with the second-wavelength laser reflected by the second reflector from the second laser and converges on the laser focusing lens.

4. A multi-band laser confocal silicon carbide ingot processing device according to claim 1, characterized in that, It further includes a positioning area. Above the positioning area, there are several concentric ring-shaped positioning lights for projecting several positioning rings for positioning the stage and the ingot to be processed in the positioning area. The stage includes a processing seat and a circular vacuum chuck. The processing seat is installed on the C-axis module, and the vacuum chuck is arranged on the processing seat for fixing the ingot to be processed in a vacuum adsorption manner, and the center of the vacuum chuck is located on the rotating shaft of the processing seat. The processing seat positions the centers of the vacuum chuck and the ingot to be processed at the centers of the corresponding positioning rings respectively under the drive of the X-axis movement module and the Y-axis movement module for positioning.

5. A multi-band laser confocal silicon carbide ingot processing device according to claim 4, characterized in that, Support columns are provided on the positioning area, and a second Z-axis moving module is provided on the support columns. A number of the annular positioning lights are installed on the second Z-axis moving module, and the second Z-axis moving module drives the annular positioning lights to move up and down along the support columns to project positioning rings with the same center but different diameters, so as to adapt to the processing of ingots with different diameters.

6. The multi-band laser confocal silicon carbide ingot processing equipment according to claim 1, wherein, The B-axis module includes a swing motor, a swing plate and a swing arm. One end of the swing plate is perpendicularly connected to the output shaft of the swing motor, and the other end is perpendicularly connected to the swing arm; the C-axis module includes a rotation motor and a processing seat. The rotation motor is installed on the swing arm, the processing seat is drivingly connected to the rotation motor, and the rotation axis of the processing seat is perpendicular to the rotation axis of the swing motor.

7. A processing method for a multi-band laser confocal silicon carbide ingot, which uses the multi-band laser confocal silicon carbide ingot processing equipment described in any one of claims 1 to 6, and is characterized in that, It includes the following steps: S1. Parameter settings are performed on the control system. The set parameters include the diameter and thickness of the final ingot product, the parameters of the V-shaped cutting groove, the laser parameters, and the rotation speed n of the C-axis module. The control system calculates the deflection angle α of the B-axis module according to the set parameters, automatically plans the laser cutting path for layer-by-layer processing, and calculates the processing time. The parameters of the V-shaped cutting groove include the maximum width L of the V-shaped cutting groove, the included angle β between the two sides of the V-shaped cutting groove, and the laser depth step amount H. The laser depth step amount H is the distance between two adjacent upper and lower layers during layer-by-layer processing. The laser parameters include laser power, laser frequency, pulse width, and duty cycle; the deflection angle α = θ / 2, where θ is the cone angle of the conical laser beam. , D is the beam diameter incident on the laser focusing lens, W D is the distance between the laser focusing lens and the laser focus; S2. The ingot to be processed is moved and positioned to the processing area through the X-axis moving module and the Y-axis moving module. Then, according to the deflection angle α, the B-axis module is controlled to swing the ingot to be processed in the vertical direction so that the included angle between its vertical central axis and the vertical direction is α. Then, the laser generated by the laser component is focused on the surface of the ingot to be processed through the CCD automatic focusing system, and the side surface of the ingot is cut according to the planned laser cutting path. S3. After the side surface of the ingot is cut, the control system controls the B-axis module to swing the ingot in the vertical direction so that its vertical central axis returns to the vertical direction, focuses the laser on the surface of the ingot to be processed, and cooperates with the movements of the X-axis moving module, the Y-axis moving module and the C-axis module to process the top surface or the bottom surface of the ingot according to the planned laser processing path.

8. A method for processing a multi-band laser confocal silicon carbide ingot according to claim 7, characterized in that, In the laser cutting path of layer-by-layer machining described in step S1, the width of each layer gradually narrows from top to bottom, and the V-shaped cutting groove is finally formed on the vertical section. The included angle β between the two sides of the V-shaped cutting groove is equal to θ, where θ is the cone angle of the conical laser beam. , where D is the beam diameter incident on the laser focusing lens, and W D is the distance between the laser focusing lens and the laser focus; during the machining of each layer, a path of machining in one ring after another from the inside to the outside or from the outside to the inside is adopted. The parameters of the laser cutting path include the processing width L of each layer n , the laser width step M, and the laser moving speed V. The processing width L of each layer is the processing width of each layer during layer-by-layer processing. The laser width step M is the step between adjacent rings when the laser processes layer by layer in rings. The laser moving speed V is the linear speed of cutting when the laser processes in rings, and V = πr·n / 30, mm / s, where r is the radius of gyration at the cutting point, mm; π is the constant 3.14, dimensionless; n is the rotational speed of the C-axis rotation, revolutions / minute.

9. A method for processing a multi-band laser confocal silicon carbide ingot according to claim 7, characterized in that, The method of moving and positioning the ingot to be processed to the processing area through the X-axis moving module and the Y-axis moving module in step S2 is as follows: A number of concentric annular positioning lights that can be lifted and moved are provided above the positioning area. The carrier table includes a processing seat and a circular vacuum chuck. The processing seat is installed on the C-axis module, the vacuum chuck is provided on the processing seat, and the center of the vacuum chuck is located on the rotation axis of the processing seat. The height of the annular positioning lights is adjusted according to the size of the ingot to be processed, and positioning rings corresponding to the vacuum chuck and the size of the corresponding ingot are projected in the positioning area respectively. First, the vacuum chuck is moved to the corresponding positioning ring by controlling the X-axis moving module and the Y-axis moving module. After the center of the vacuum chuck coincides with the center of gravity of the positioning ring corresponding to the vacuum chuck, the ingot to be processed is placed on the vacuum chuck so that the center of the ingot to be processed coincides with the center of the positioning ring corresponding to the ingot. Then, the ingot to be processed is fixed by means of vacuum adsorption, and then the Y-axis moving module is controlled to move the ingot to be processed to the processing area under the laser component.

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