A laser cutting device for automatically correcting the deviation of the uneven surface of a wafer

Abstract

The present invention provides a laser cutting device capable of automatically correcting the unevenness of a wafer surface. Before a host computer controls a mobile driving module to drive a cutting machine frame to drive a laser generating unit to irradiate a laser beam and pass through an object to be cut along a cutting track, the present invention can obtain the thickness and inclination of all parts of the cutting track and the distance between the laser generating unit and each part of the cutting track through a distance meter. Therefore, when the laser slides through all parts of the cutting track, the lens driving module can drive the objective lens distance between lens groups to adjust the laser focal length, so that the laser can stably, completely and concentratedly fall on all parts of the cutting track, thereby stably cutting an object to be cut with an uneven surface, different thicknesses at various parts, and different inclined parts on the surface. The present invention belongs to the technical field of automation equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of automated equipment, and particularly relates to a laser cutting device for automatically correcting the unevenness on the surface of a wafer. Background Art

[0002] With the rapid rise of industries such as artificial intelligence, intelligent manufacturing, automotive electronics, Internet of Things, and 5G communication, integrated circuits, as the core hardware of these industries, have also become the core of the development of China's information technology. Therefore, the integrated circuit industry has been developing rapidly, with both the market scale and technical level continuously improving. As a type of integrated circuit, chip manufacturing has also become one of the rapidly developing industries.

[0003] Wafer cutting is an important link in the chip manufacturing process, and its technical precision and efficiency directly affect the performance and cost of the chip. Compared with mechanical cutting, laser cutting is to make the focused laser beam irradiate on the surface of the wafer. The laser energy is absorbed by the wafer material and converted into heat energy, causing the local area to quickly melt or evaporate, thereby forming a cutting channel. This process is fast and precise, and can achieve a cutting accuracy at the micron level. In addition, since laser cutting is non-contact, it avoids the influence of mechanical stress on the wafer and reduces the generation of cracks and fragments. Therefore, this characteristic makes laser cutting particularly suitable for processing fragile or ultra-thin wafers. In recent years, with the continuous progress of laser technology, optical technology, precision machinery technology, etc., the precision, speed, and stability of wafer cutting equipment have been significantly improved.

[0004] Since traditional wafer cutting adsorbs the wafer to be cut on a vacuum platform, after manually or actually calibrating the cutting path, the platform or the cutting laser head above is moved along the cutting path for cutting. At this time, the height of the laser head is a fixed value and only moves along the axis parallel to the cutting path. However, this cutting mode faces two problems: 1. The levelness of the vacuum platform depends on the accuracy during the platform design and assembly, and it is impossible to ensure its complete levelness; 2. In fact, the surface of the wafer is not completely flat, and there may be uneven thickness and undulations at different positions on a cutting path. Since the principle of laser cutting is to cut by focusing the laser on the surface of the wafer, the above two problems will cause the laser focus not to necessarily fall exactly on the surface of the wafer during actual cutting, resulting in unstable quality of the cutting path. Summary of the Invention

[0005] The purpose of the present invention is to provide a laser cutting device for automatically correcting the unevenness on the surface of a wafer to solve the technical defects described in the background art.

[0006] The purpose of the present invention is to provide a laser cutting device for automatically correcting the unevenness on the surface of a wafer to solve the technical defects of the background art.

[0007] A laser cutting device for automatically correcting the deviation of the uneven surface of a wafer includes:

[0008] A cutting platform for placing the object to be cut;

[0009] A moving drive module for driving the movement of the cutting machine frame. A distance measuring instrument and a laser generating unit are installed on the cutting machine frame. The distance measuring instrument is perpendicular to the cutting platform, and the laser generating unit is parallel to the distance measuring instrument, so that the laser emitted by the laser generating unit irradiates the object to be cut placed on the cutting platform. There is a constant distance between the laser generating unit and the distance measuring instrument in parallel;

[0010] A lens group is located between the laser generating unit and the cutting platform. The lens group is provided with a lens drive module. The lens drive module includes a rack and a gear. The rack is fixedly arranged, and a number of electromagnets with S poles and N poles arranged in a staggered manner are arrayed on the rack. The bearing of the gear is fixed to the objective lens of the lens group, and the gear meshes with the rack. A number of magnets with S poles and N poles arranged in a staggered manner are arrayed on the outer periphery of the gear. By energizing a certain electromagnet on the rack, the electromagnet adsorbs the magnet corresponding to its magnetic pole on the gear, so as to drive the gear to move on the rack and fix the gear at a certain position on the rack, so that the distance between the objective lenses of the lens group can be driven by the lens drive module according to the distance monitored by the distance measuring instrument between it and the object to be cut, and the laser focal length can be adjusted.

[0011] Based on the above technical solutions, the present invention further realizes the following beneficial effects:

[0012] 1. When the laser slides over the cutting part of the object to be cut, the distance between it and the object to be cut is monitored in advance by the distance measuring instrument, and then the distance between the objective lenses of the lens group is driven by the lens drive module, so as to adjust the laser focal length, so that the laser can stably, completely and intensively fall on the cutting part, so as to stably cut the object to be cut with an uneven surface, different thicknesses at each part, and different inclined parts on the surface;

[0013] 2. Since a number of electromagnets with S poles and N poles arranged in a staggered manner are arrayed on the rack, and at the same time, a number of magnets with S poles and N poles arranged in a staggered manner are arrayed on the outer periphery of the gear, therefore, by respectively energizing the electromagnets with S poles or N poles, at this time, the suction force of the electromagnets near the gear adsorbs the magnets near its periphery, so as to drive the gear to move to a certain position on the rack. When the gear moves, the gear drives the objective lens to move, so as to realize the adjustment of the distance between multiple objective lenses and the distance between the objective lens and the laser generating unit, so as to adjust the laser focal length;

[0014] 3. Since the electromagnets on the rack are arranged with S poles and N poles staggered, and the magnets on the periphery of the gear are also arranged with S poles and N poles staggered, the gear can be driven to move on the rack by the principle of repulsion of like magnetic fields of magnets;

[0015] 4. Since the gear is driven to move on the rack by adsorbing the magnet on the periphery of the gear through the electromagnet, when the gear moves to a certain position of the rack, the magnet can be adsorbed by the electromagnet, thereby fixing the gear to a certain position of the rack, that is, fixing the position of the material objective lens.

[0016] In order to further optimize the above technical solution, it can be optionally combined with one or more of the following implementation methods without conflict.

[0017] In some embodiments, the laser cutting device for automatically correcting the unevenness of the wafer surface further includes:

[0018] The control system includes a host computer and an analog quantity acquisition card. The host computer is connected to the analog quantity acquisition card and the mobile drive module by signal. The analog quantity acquisition card is respectively connected to the rangefinder and the lens drive module by electrical signals. The host computer controls the mobile drive module to drive the cutting machine frame to drive the laser irradiated by the laser generating unit to pass through the object to be cut along the cutting track. Before the rangefinder passes over the cutting track in advance, the analog quantity acquisition card obtains the distance between the cutting machine frame and a certain part of the cutting track through the rangefinder in advance, so as to calculate the distance between the laser generating unit and the part, the thickness of the part and the inclination of the object to be cut. Therefore, when the laser is drawn to the part, the time when the laser irradiated by the laser generating unit reaches the part after the rangefinder passes through the certain part of the cutting track is calculated through the distance between the laser generating unit and the rangefinder and the moving speed of the cutting machine frame driven by the mobile drive module. Thereafter, the analog quantity acquisition card controls the lens drive module to drive the objective lens distance between the lens groups, thereby adjusting the laser focal length;

[0019] Based on the above technical solution, the present invention further achieves the following beneficial effects:

[0020] Because before the upper computer controls the mobile drive module to drive the cutting machine frame to drive the laser generating unit to irradiate the laser to pass through the object to be cut along the cutting track, the thickness and inclination of all parts of the cutting track and the distance between the laser generating unit and each part of the cutting track can be obtained through the rangefinder. Therefore, when the laser slides through all parts of the cutting track, the objective lens distance between the lens groups can be driven by the lens drive module, and the laser focal length can be adjusted so that the laser can fall stably, completely and concentratedly on all parts of the cutting track, thereby stably cutting the object to be cut with an uneven surface, different thicknesses in different parts, and different inclinations on the surface.

[0021] In some embodiments, the electromagnet is electrically connected to the analog acquisition card, and the analog acquisition card is used to energize the electromagnets located near the gear separately and independently;

[0022] Based on the above technical solutions, the present invention can further achieve the following beneficial effects:

[0023] 1. Since the analog acquisition card is used to energize the electromagnets located near the gear separately and independently, it is possible to more stably and accurately move the gear to a certain position on the rack by the suction or repulsive force of the magnetic field generated by the electromagnets near the gear, and to stably fix the gear on the rack;

[0024] 2. Since the electromagnets other than those near the gear can be de-energized, the interference of the electromagnets other than those near the gear to the electromagnets near the gear can be avoided, so as to more stably drive the gear to move.

[0025] In some embodiments, the lens group is provided with a plurality of objective lenses, each objective lens is fixedly supported by a gear meshing with the rack, and the lens driving module further includes a lens positioning unit, and the lens positioning unit is used to obtain the position of each gear on the rack;

[0026] Based on the above technical solutions, the present invention can further achieve the following beneficial effects:

[0027] 1. Since each electromagnet can be energized independently through the analog acquisition card, and at the same time, each objective lens is fixedly supported by a gear meshing with the rack, it is possible to independently drive each gear on the rack to move, that is, to independently drive each objective lens to move;

[0028] 2. Since all the gears move on the same rack, that is, it is not necessary to set multiple motors to independently drive each objective lens to move, thereby reducing the volume of the device and the manufacturing cost of the device;

[0029] 3. When driving each objective lens to move independently, in combination with the lens positioning unit to position each objective lens and control the operation of each electromagnet, so as to accurately adjust the distance between multiple objective lenses and the distance between the objective lens and the laser generating unit;

[0030] 4. Compared with the traditional motor driving the gear to rotate, since the motor drives the gear to rotate in a step-by-step manner of the stroke, while the present invention controls the rotation of the gear by applying a specific electric energy to the electromagnet and using the magnetic field generated by the electromagnet, and since the selection range of the current can be infinite and the adjustment of the current can be infinitely fine, the present invention can drive the gear to rotate more accurately compared with the motor.

[0031] In some embodiments, each electromagnet is provided with a filter, and the power frequency bands output by each filter are different from those output by all the other filters, so that each electromagnet can only receive the power of the corresponding frequency band. The analog acquisition card is electrically connected in parallel with all the filters, so that the analog acquisition card can combine and output the power of different frequency bands delivered to each electromagnet;

[0032] Based on the above technical solutions, the present invention further achieves the following beneficial effects:

[0033] There is no need to provide each electromagnet with a cable independently connected to the analog acquisition card. Instead, all the electromagnets can be connected in parallel with the analog acquisition card through a single set of cables, and each electromagnet can also be independently controlled, thereby reducing the wiring difficulty, reducing the difficulty of control line logic, and reducing the wire usage.

[0034] In some embodiments, a frequency divider electrically connected to each electromagnet is installed on the rack. The power frequency bands output by the frequency divider to each electromagnet are all different. The frequency divider is electrically connected to the analog acquisition card, so that the analog acquisition card can combine and output the power of different frequency bands delivered to each electromagnet to the frequency divider;

[0035] Based on the above technical solutions, the present invention further achieves the following beneficial effects:

[0036] By electrically connecting the frequency divider to each electromagnet, it is not necessary to set cables separately and independently connected to each electromagnet for the analog acquisition card. Instead, it only needs to be connected to the analog acquisition card through a single set of cables, and each electromagnet can be independently controlled, thereby reducing the wiring difficulty, reducing the difficulty of control line logic, and reducing the wire usage.

[0037] In some embodiments, the lens group is provided with a slide rail, the slide rail is fixedly arranged, and the objective lens is installed with a slider sliding on the slide rail;

[0038] Based on the above technical solutions, the gear can move linearly on the rack more stably, and the objective lenses can also move linearly stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the specific embodiments in the present invention, the following will briefly describe the drawings and reference numerals required in the description of the specific embodiments.

[0040] Figure 1 is a schematic structural diagram of the cutting machine frame of the present invention;

[0041] Figure 2 is a circuit block diagram of the control system of the present invention;

[0042] Figure 3It is a schematic diagram of the positions of the racks described in Embodiments 2 and 3;

[0043] Figure 4 It is a schematic diagram of the position of the electromagnet described in Embodiment 2;

[0044] Figure 5 It is a schematic diagram of the position of the electromagnet described in Embodiment 3.

[0045] Reference numerals:

[0046] 1. Cutting platform; 12. Object to be cut; 13. Cutting trajectory; 2. Moving drive module; 21. Cutting machine frame; 22. Rangefinder; 23. Laser generating unit; 3. Lens group; 31. Objective lens; 41. Rack; 411. Electromagnet; 412. Filter; 413. Frequency divider; 42. Gear; 421. Magnet; 43. Slide rail; 44. Slide block; 5. Host computer; 51. Analog acquisition card. Detailed implementation manners

[0047] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present detailed implementation manner will further describe the present invention in detail with reference to the accompanying drawings.

[0048] As Figures 1 to 5 shown, the present detailed implementation manner provides a laser cutting device for automatically correcting the unevenness on the surface of a wafer, which includes a cutting platform 1, a moving drive module 2 and a control system.

[0049] Cutting platform 1, the cutting platform 1 is used for placing the object to be cut 12.

[0050] Moving drive module 2, the moving drive module 2 is used to drive the cutting machine frame 21 to move. The cutting machine frame 21 is equipped with a rangefinder 22 and a laser generating unit 23. The rangefinder 22 is perpendicular to the cutting platform 1, and the laser generating unit 23 is parallel to the rangefinder 22, so that the laser emitted by the laser generating unit 23 irradiates the object to be cut 12 placed on the cutting platform 1. There is a constant distance between the laser generating unit 23 and the rangefinder 22 being parallel. A lens group 3 is provided between the laser generating unit 23 and the cutting platform 1. The lens group 3 is provided with a lens driving module, and the lens driving module is used to drive the distance between the objective lenses 31 in the lens group 3.

[0051] The control system includes a host computer 5 and an analog quantity acquisition card 51. The host computer 5 is connected to the analog quantity acquisition card 51 and the mobile drive module 2 by signal. The analog quantity acquisition card 51 is respectively connected to the rangefinder 22 and the lens drive module by electrical signal. The host computer 5 controls the mobile drive module 2 to drive the cutting machine frame 21 to drive the laser generating unit 23 to irradiate the laser before passing through the object 12 to be cut along the cutting track 13. The rangefinder 22 passes over the cutting track 13 in advance, so that the analog quantity acquisition card 51 obtains the distance between the cutting machine frame 21 and a certain part of the cutting track 13 through the rangefinder 22 in advance. The distance between the positions is used to calculate the distance between the laser generating unit 23 and the position, the thickness of the position and the inclination of the object 12 to be cut. Therefore, when the laser reaches the position, the time for the laser irradiated by the laser generating unit 23 to reach the position after the rangefinder 22 passes through a certain position of the cutting track 13 is calculated through the distance between the laser generating unit 23 and the rangefinder 22 and the moving speed of the cutting machine frame 21 driven by the mobile driving module 2. After that, the analog quantity acquisition card 51 controls the lens driving module to drive the distance between the objective lens 31 of the lens group 3 to adjust the laser focal length.

[0052] Before the upper computer 5 controls the mobile driving module 2 to drive the cutting machine frame 21 to drive the laser generating unit 23 to irradiate the laser to pass through the object 12 to be cut along the cutting track 13, the thickness and inclination of all parts of the cutting track 13 and the distance between the laser generating unit 23 and each part of the cutting track 13 can be obtained through the rangefinder 22. Therefore, when the laser slides through all parts of the cutting track 13, the distance of the objective lens 31 between the lens groups 3 can be driven by the lens driving module to adjust the laser focal length so that the laser can stably, completely and concentratedly fall on all parts of the cutting track 13, thereby stably cutting the object 12 to be cut with an uneven surface, different thicknesses in different parts, and different inclinations on the surface.

[0053] In some embodiments, the lens driving module is a motor, which is used as a power source to drive the screw of the screw module to rotate to achieve the distance between the objective lens 31 of the lens group 3.

[0054] In some embodiments, the lens driving module includes a rack 41 and a gear 42. The rack 41 is fixedly arranged. An array of several electromagnets 411 with staggered S and N poles is arranged on the rack 41. The electromagnet 411 is electrically connected to the analog quantity acquisition card 51. The bearing of the gear 42 is fixed on the objective lens 31 of the lens group 3. The gear 42 is meshed with the rack 41. The outer peripheral array of the gear 42 has several magnets 421 with staggered S and N poles. The analog quantity acquisition card 51 is used to independently energize the electromagnet 411 located near the gear 42, so that the electromagnet 411 near the gear 42 absorbs the magnet 421 near its periphery, thereby driving the gear 42 to move on the rack 41 and fixing the gear 42 at a certain position of the rack 41.

[0055] The analog acquisition card 51 is used to independently energize the electromagnet 411 located near the gear 42 and control the electromagnet 411 far from the vicinity of the gear 42 to be de-energized, so that the suction force of the electromagnet 411 near the gear 42 adsorbs the magnet 421 near its periphery, driving the gear 42 to move on the rack 41 to a certain position on the rack 41. When the gear 42 moves, the gear 42 drives the objective lens 31 to move, realizing the adjustment of the distance between multiple objective lenses 31 and the distance between the objective lens 31 and the laser generating unit 23, thereby adjusting the laser focal length.

[0056] The electromagnets 411 on the rack 41 are arranged with S poles and N poles staggered, and at the same time, the magnets 421 on the outer periphery of the gear 42 are also arranged with S poles and N poles staggered. Therefore, the principle of repulsion of like magnetic fields of the magnet 421 can be used to drive the gear 42 to move on the rack 41.

[0057] The electromagnet 411 adsorbs the magnet 421 on the outer periphery of the gear 42 to drive it to move on the rack 41. When the gear 42 moves to a certain position on the rack 41, the electromagnet 411 can adsorb the magnet 421, thereby fixing the gear 42 to a certain position on the rack 41, that is, realizing the fixation of the position of the objective lens 31 of the material.

[0058] In some embodiments, the lens group 3 is provided with a plurality of objective lenses 31, and each objective lens 31 is fixedly supported by a gear 42 meshing with the rack 41. The lens driving module further includes a lens positioning unit for obtaining the position of each gear 42 on the rack 41.

[0059] The analog acquisition card 51 independently energizes each electromagnet 411. At the same time, each objective lens 31 is fixedly supported by a gear 42 meshing with the rack 41. Therefore, each gear 42 on the rack 41 is independently driven to move, that is, each objective lens 31 is independently driven to move. All the gears 42 move on the same rack 41, that is, it is possible to independently drive each objective lens 31 to move without setting multiple motors, thereby reducing the volume of the device and the manufacturing cost of the device.

[0060] When driving each objective lens 31 to move independently, the lens positioning unit is combined to position each objective lens 31 and control the operation of each electromagnet 411, thereby realizing the precise adjustment of the distance between multiple objective lenses 31 and the distance between the objective lens 31 and the laser generating unit 23.

[0061] In some embodiments, each electromagnet 411 is provided with a filter 412. The power frequency bands output by each filter 412 are different from those of all the other filters 412, so that each electromagnet 411 can only receive the power of the corresponding frequency band. The analog acquisition card 51 is electrically connected in parallel with all the filters 412, so that the analog acquisition card 51 can combine and output the different frequency band power supplied to each electromagnet 411.

[0062] There is no need to provide each electromagnet 411 with a cable independently connected to the analog acquisition card 51. Instead, all the electromagnets 411 and the analog acquisition card 51 can be connected in parallel through a single set of cables, and each electromagnet 411 can still be independently controlled, thus reducing the wiring difficulty, the difficulty of control line logic, and the wire consumption.

[0063] In some embodiments, a frequency divider 413 electrically connected to each electromagnet 411 is installed on the rack 41. The power frequency bands output by the frequency divider 413 to each electromagnet 411 are all different. The frequency divider 413 is electrically connected to the analog acquisition card 51, so that the analog acquisition card 51 can combine and output the different frequency band power supplied to each electromagnet 411 to the frequency divider 413.

[0064] The frequency divider 413 is electrically connected to each electromagnet 411, so that there is no need to set cables separately and independently connected to each electromagnet 411 for the connection of the analog acquisition card 51. Instead, it only needs to be connected to the analog acquisition card 51 through a single set of cables, and each electromagnet 411 can be independently controlled, thus reducing the wiring difficulty, the difficulty of control line logic, and the wire consumption.

[0065] In some embodiments, the lens group 3 is provided with a slide rail 43. The slide rail 43 is fixedly arranged. The objective lens 31 is installed with a slider 44 sliding on the slide rail 43, so that the gear 42 can move linearly on the rack 41 more stably, and the objective lenses 31 can also move linearly stably.

[0066] To further illustrate the laser cutting device for automatic deviation correction of the unevenness on the wafer surface described in this specific embodiment, the following embodiments are listed to introduce the laser cutting device. Embodiment

[0067] As Figure 1 and 2 shown, this embodiment provides a laser cutting device for automatic deviation correction of the unevenness on the wafer surface, which includes a cutting platform 1, a moving drive module 2, a cutting machine frame 21, and a control system.

[0068] Cutting platform 1, the cutting platform 1 is used to place the object to be cut 12.

[0069] A mobile driving module 2 is used to drive the cutting machine frame 21 to move. The cutting machine frame 21 is installed with a rangefinder 22 and a laser generating unit 23. The rangefinder 22 is perpendicular to the cutting platform 1. The laser generating unit 23 is parallel to the rangefinder 22, so that the laser emitted by the laser generating unit 23 can irradiate the object to be cut 12 placed on the cutting platform 1. The laser generating unit 23 is parallel to the rangefinder 22 and there is a constant distance between them. A lens group 3 is provided between the laser generating unit 23 and the cutting platform 1. The lens group 3 is provided with a lens driving module. The lens driving module is used to drive the distance of the objective lens 31 between the lens groups 3.

[0070] The lens driving module is a motor. When the motor is used as a power source, the objective lens 31 in the lens group 3 is fixed with a slider 44 and a nut. The motor is connected to a lead screw, which is threadedly connected to the nut. The slider 44 slides on the slide rail 43, which is fixedly connected. When the motor drives the lead screw to rotate, the lead screw can drive the objective lens 31 to move.

[0071] The control system includes a host computer 5 and an analog quantity acquisition card 51. The host computer 5 is connected to the analog quantity acquisition card 51 and the mobile drive module 2 by signals. The analog quantity acquisition card 51 is respectively connected to the rangefinder 22 and the lens drive module by electrical signals. The host computer 5 controls the mobile drive module 2 to drive the cutting machine frame 21 to drive the laser generating unit 23 to irradiate the laser before passing through the object 12 to be cut along the cutting track 13. The rangefinder 22 passes over the cutting track 13 in advance, so that the analog quantity acquisition card 51 obtains the distance between the cutting machine frame 21 and a certain part of the cutting track 13 through the rangefinder 22 in advance, so as to calculate the distance between the laser generating unit 23 and the cutting track 13. 23 and the part, the thickness of the part and the inclination of the object 12 to be cut, so that when the laser reaches the part, the time for the laser irradiated by the laser generating unit 23 to reach the part after the rangefinder 22 passes through a certain part of the cutting track 13 is calculated through the distance between the laser generating unit 23 and the rangefinder 22 and the moving speed of the cutting machine assembly frame 21 driven by the mobile driving module 2. After that, the analog quantity acquisition card 51 controls the lens driving module to drive the objective lens 31 between the lens groups 3 to move, thereby adjusting the distance between the objective lenses 31 and the distance between the objective lens 31 and the laser generating unit 23, and adjusting the laser focal length. Example

[0072] like Figure 1 and 3 As shown, this embodiment provides a laser cutting device for automatically correcting the unevenness of a wafer surface, which includes a cutting platform 1, a mobile drive module 2, a cutting machine frame 21 and a lens group 3.

[0073] A cutting platform 1, the cutting platform 1 is used to place an object 12 to be cut;

[0074] The moving drive module 2 is used to drive the movement of the cutting machine frame 21. A distance measuring instrument 22 and a laser generating unit 23 are installed on the cutting machine frame 21. The distance measuring instrument 22 is perpendicular to the cutting platform 1, and the laser generating unit 23 is parallel to the distance measuring instrument 22, so that the laser emitted by the laser generating unit 23 irradiates the object to be cut 12 placed on the cutting platform 1. There is a constant distance between the laser generating unit 23 and the distance measuring instrument 22 being parallel.

[0075] The lens group 3 is located between the laser generating unit 23 and the cutting platform 1. The lens group 3 is provided with a lens driving module. The lens driving module includes a rack 41 and a gear 42. The rack 41 is fixedly arranged, and a number of electromagnets 411 with S poles and N poles arranged in a staggered manner are arrayed on the rack 41. The gear 42 is fixedly mounted on the objective lens 31 of the lens group 3 by a bearing. The gear 42 meshes with the rack 41. A number of magnets 421 with S poles and N poles arranged in a staggered manner are arrayed on the outer periphery of the gear 42. By respectively energizing the electromagnets 411 with S poles or N poles, the electromagnets 411 adsorb the magnets 421 on the gear 42, so as to drive the gear 42 to move on the rack 41 and fix the gear 42 at a certain position on the rack 41, so that the distance between the objective lens 31 of the lens group 3 can be driven by the lens driving module according to the distance monitored by the distance measuring instrument 22 between it and the object to be cut 12, and the laser focal length can be adjusted.

[0076] When the laser slides across the cutting part of the object to be cut 12, first, the distance between it and the object to be cut 12 is monitored by the distance measuring instrument 22, and then the distance between the objective lenses 31 of the lens group 3 is driven by the lens driving module, so as to adjust the laser focal length, so that the laser can stably, completely and intensively fall on the cutting part, so as to stably cut the object to be cut 12 with an uneven surface, different thicknesses at each part, and different inclined parts on the surface; further, because a number of electromagnets 411 with S poles and N poles arranged in a staggered manner are arrayed on the rack 41, and at the same time, a number of magnets 421 with S poles and N poles arranged in a staggered manner are arrayed on the outer periphery of the gear 42, therefore, by respectively energizing the electromagnets 411 with S poles or N poles, at this time, the suction force of the electromagnets 411 near the gear 42 adsorbs the magnets 421 near its periphery, so as to drive the gear 42 to move to a certain position on the rack 41. When the gear 42 moves, the gear 42 drives the objective lens 31 to move, so as to adjust the distance between multiple objective lenses 31 and the distance between the objective lens 31 and the laser generating unit 23, so as to adjust the laser focal length.

[0077] The electromagnets 411 on the rack 41 are arranged with S poles and N poles in a staggered manner, and at the same time, the magnets 421 on the outer periphery of the gear 42 are also arranged with S poles and N poles in a staggered manner. Therefore, the movement of the gear 42 on the rack 41 can be realized by the principle of repulsion of the same-sex magnetic fields of the magnets 421.

[0078] When adjusting the focal length, the electromagnet 411 attracts the magnet 421 on the periphery of the gear 42 to drive the rack 41 to move. When the gear 42 moves to a certain position of the rack 41, the electromagnet 411 can attract the magnet 421 to fix the gear 42 to a certain position of the rack 41, that is, to fix the position of the material objective lens 31. Example

[0079] like Figures 1 to 4 As shown, this embodiment provides a laser cutting device for automatically correcting the unevenness of a wafer surface, which includes a cutting platform 1, a mobile drive module 2, a cutting machine frame 21 and a control system.

[0080] The cutting platform 1 is used to place an object 12 to be cut.

[0081] A mobile driving module 2 is used to drive the cutting machine frame 21 to move. The cutting machine frame 21 is installed with a rangefinder 22 and a laser generating unit 23. The rangefinder 22 is perpendicular to the cutting platform 1. The laser generating unit 23 is parallel to the rangefinder 22, so that the laser emitted by the laser generating unit 23 can irradiate the object to be cut 12 placed on the cutting platform 1. The laser generating unit 23 is parallel to the rangefinder 22 and there is a constant distance between them. A lens group 3 is provided between the laser generating unit 23 and the cutting platform 1. The lens group 3 is provided with a lens driving module. The lens driving module is used to drive the distance of the objective lens 31 between the lens groups 3.

[0082] The control system includes a host computer 5 and an analog quantity acquisition card 51. The host computer 5 is connected to the analog quantity acquisition card 51 and the mobile drive module 2 by signals. The analog quantity acquisition card 51 is respectively connected to the rangefinder 22 and the lens drive module by electrical signals. The host computer 5 controls the mobile drive module 2 to drive the cutting machine frame 21 to drive the laser generating unit 23 to irradiate the laser before passing through the object 12 to be cut along the cutting track 13. The rangefinder 22 passes over the cutting track 13 in advance, so that the analog quantity acquisition card 51 obtains the distance between the cutting machine frame 21 and a certain part of the cutting track 13 through the rangefinder 22 in advance, so as to calculate the distance between the laser generating unit 23 and the cutting track 13. 23 and the part, the thickness of the part and the inclination of the object 12 to be cut, so that when the laser reaches the part, the time for the laser irradiated by the laser generating unit 23 to reach the part after the rangefinder 22 passes through a certain part of the cutting track 13 is calculated through the distance between the laser generating unit 23 and the rangefinder 22 and the moving speed of the cutting machine assembly frame 21 driven by the mobile driving module 2. After that, the analog quantity acquisition card 51 controls the lens driving module to drive the objective lens 31 between the lens groups 3 to move, thereby adjusting the distance between the objective lenses 31 and the distance between the objective lens 31 and the laser generating unit 23, and adjusting the laser focal length.

[0083] The lens driving module includes a rack 41 and a slide rail 43. The rack 41 is fixedly arranged, and a plurality of electromagnets 411 with S poles and N poles arranged in a staggered manner are arrayed on the rack 41. The electromagnets 411 are electrically connected to an analog acquisition card 51. A gear 42 is connected to the objective lens 31 through a bearing. The gear 42 meshes with the rack 41. A plurality of magnets 421 with S poles and N poles arranged in a staggered manner are arrayed on the outer periphery of the gear 42. The analog acquisition card 51 is used to independently energize the electromagnets 411 near the gear 42, so that the electromagnets 411 near the gear 42 adsorb the magnets 421 near their peripheries, thereby driving the gear 42 to move on the rack 41 and fixing the gear 42 at a certain position on the rack 41. The slide rail 43 is fixedly arranged, and the objective lens 31 is equipped with a slider 44 that slides on the slide rail 43, so that the gear 42 can move linearly on the rack 41 more stably, and the objective lenses 31 can also move linearly stably.

[0084] When the lens group 3 is provided with a plurality of objective lenses 31, each objective lens 31 is fixedly connected to a gear 42 meshing with the rack 41 through a bearing, and a slider 44 sliding on the slide rail 43. The lens driving module further includes a lens positioning unit for obtaining the position of each gear 42 on the rack 41. The lens positioning unit can obtain the distance of its lens through an infrared rangefinder 22 so as to position the objective lens 31.

[0085] Each electromagnet 411 is provided with a filter 412. The power frequency bands output by each filter 412 are different from those of all the other filters 412, so that each electromagnet 411 can only receive electrical energy of the corresponding frequency band. The analog acquisition card 51 is electrically connected in parallel with all the filters 412, so that the analog acquisition card 51 can merge and output the different frequency band electrical energies delivered to each electromagnet 411. Embodiment

[0086] As Figures 1 to 3 、and Figure 5 shown, this embodiment provides a laser cutting device for automatically correcting the unevenness on the surface of a wafer, which includes a cutting platform 1, a moving driving module 2, a cutting machine frame 21, and a control system.

[0087] The cutting platform 1 is used to place the object to be cut 12.

[0088] A mobile driving module 2 is used to drive the cutting machine frame 21 to move. The cutting machine frame 21 is installed with a rangefinder 22 and a laser generating unit 23. The rangefinder 22 is perpendicular to the cutting platform 1. The laser generating unit 23 is parallel to the rangefinder 22, so that the laser emitted by the laser generating unit 23 can irradiate the object to be cut 12 placed on the cutting platform 1. The laser generating unit 23 is parallel to the rangefinder 22 and there is a constant distance between them. A lens group 3 is provided between the laser generating unit 23 and the cutting platform 1. The lens group 3 is provided with a lens driving module. The lens driving module is used to drive the distance of the objective lens 31 between the lens groups 3.

[0089] The control system includes a host computer 5 and an analog quantity acquisition card 51. The host computer 5 is connected to the analog quantity acquisition card 51 and the mobile drive module 2 by signals. The analog quantity acquisition card 51 is respectively connected to the rangefinder 22 and the lens drive module by electrical signals. The host computer 5 controls the mobile drive module 2 to drive the cutting machine frame 21 to drive the laser generating unit 23 to irradiate the laser before passing through the object 12 to be cut along the cutting track 13. The rangefinder 22 passes over the cutting track 13 in advance, so that the analog quantity acquisition card 51 obtains the distance between the cutting machine frame 21 and a certain part of the cutting track 13 through the rangefinder 22 in advance, so as to calculate the distance between the laser generating unit 23 and the cutting track 13. 23 and the part, the thickness of the part and the inclination of the object 12 to be cut, so that when the laser reaches the part, the time for the laser irradiated by the laser generating unit 23 to reach the part after the rangefinder 22 passes through a certain part of the cutting track 13 is calculated through the distance between the laser generating unit 23 and the rangefinder 22 and the moving speed of the cutting machine assembly frame 21 driven by the mobile driving module 2. After that, the analog quantity acquisition card 51 controls the lens driving module to drive the objective lens 31 between the lens groups 3 to move, thereby adjusting the distance between the objective lenses 31 and the distance between the objective lens 31 and the laser generating unit 23, and adjusting the laser focal length.

[0090] The lens driving module includes a rack 41 and a slide rail 43. The rack 41 is fixedly arranged, and an array of several electromagnets 411 with staggered S and N poles is arranged on the rack 41, and the electromagnets 411 are electrically connected to the analog quantity acquisition card 51. The bearing on the objective lens 31 is connected to a gear 42, which is meshed with the rack 41. The outer peripheral array of the gear 42 has several magnets 421 with staggered S and N poles. The analog quantity acquisition card 51 is used to independently energize the electromagnet 411 located near the gear 42, so that the electromagnet 411 near the gear 42 absorbs the magnets 421 near its periphery, thereby driving the gear 42 to move on the rack 41 and fixing the gear 42 to a certain position of the rack 41. The slide rail 43 is fixedly arranged, and the objective lens 31 is equipped with a slider 44 sliding on the slide rail 43, so that the gear 42 can move more stably on the rack 41 in a straight line, and the objective lens 31 can also move stably in a straight line.

[0091] When the lens group 3 is provided with a plurality of objective lenses 31, each objective lens 31 is fixedly mounted with a gear 42 engaged with a rack 41 and a slider 44 sliding on a slide rail 43. The lens driving module further includes a lens positioning unit for obtaining the position of each gear 42 on the rack 41. The lens positioning unit can obtain the distance of its lens through an infrared rangefinder 22 so as to position the objective lens 31.

[0092] The rack 41 is provided with a frequency divider 413 electrically connected to each electromagnet 411. The power frequency bands output by the frequency divider 413 to each electromagnet 411 are all different. The frequency divider 413 is electrically connected to an analog acquisition card 51 so that the analog acquisition card 51 can combine and output the different frequency band electric energies delivered to each electromagnet 411 to the frequency divider 413.

Claims

1. A laser cutting device for automatically correcting the unevenness of a wafer surface, characterized in that: include: A cutting platform (1), wherein the cutting platform (1) is used to place an object to be cut (12); A mobile driving module (2), the mobile driving module (2) being used to drive a cutting machine frame (21) to move, the cutting machine frame (21) being equipped with a rangefinder (22) and a laser generating unit (23), the rangefinder (22) being perpendicular to the cutting platform (1), the laser generating unit (23) being parallel to the rangefinder (22), so that the laser emitted by the laser generating unit (23) irradiates the object to be cut (12) placed on the cutting platform (1), and the laser generating unit (23) and the rangefinder (22) being parallel and at a constant distance; A lens group (3), the lens group (3) being located between the laser generating unit (23) and the cutting platform (1), the lens group (3) being provided with a lens driving module, the lens driving module comprising a rack (41) and a gear (42), the rack (41) being fixedly arranged, a plurality of electromagnets (411) with S poles and N poles arranged in a staggered manner being arranged on the rack (41), a bearing of the gear (42) being fixed on the objective lens (31) of the lens group (3), the gear (42) being meshed with the rack (41), a plurality of S poles and N poles being arranged on the periphery of the gear (42) being arranged The magnets (421) are arranged in a staggered manner, and by energizing one of the electromagnets (411) on the rack (41), the electromagnet (411) attracts the magnet (421) on the gear (42) corresponding to its magnetic pole, so as to drive the gear (42) to move on the rack (41) and fix the gear (42) at a certain position of the rack (41), so that the distance between the objective lens (31) of the lens group (3) can be driven by the lens driving module according to the distance between the distance meter (22) and the object to be cut (12), thereby adjusting the laser focal length; The lens group (3) is provided with a plurality of objective lenses (31), each of the objective lenses (31) is fixed with a gear (42) meshing with the rack (41) on a bearing, and the lens driving module further comprises a lens positioning unit, which is used to obtain the position of each gear (42) on the rack (41).

2. The laser cutting device for automatically correcting the unevenness of the wafer surface according to claim 1 is characterized in that: Also includes: A control system, the control system comprising a host computer (5) and an analog quantity acquisition card (51), the host computer (5) being connected to the analog quantity acquisition card (51) and a mobile drive module (2) by signal, the analog quantity acquisition card (51) being connected to the rangefinder (22) and the lens drive module by electrical signal respectively, the host computer (5) controlling the mobile drive module (2) to drive the cutting machine assembly frame (21) to drive the laser irradiated by the laser generating unit (23) to pass through the object to be cut (12) along a cutting track (13), the rangefinder (22) passing over the cutting track (13) in advance, so that the analog quantity acquisition card (51) can obtain the cutting machine assembly frame (21) through the rangefinder (22) in advance. The distance between the laser generating unit (23) and a certain part of the cutting track (13) is calculated to calculate the distance between the laser generating unit (23) and the part, the thickness of the part and the inclination of the object (12) to be cut. When the laser reaches the part, the time when the laser irradiated by the laser generating unit (23) reaches the part after the rangefinder (22) passes through a certain part of the cutting track (13) is calculated by the distance between the laser generating unit (23) and the rangefinder (22) and the moving speed of the driving module to drive the cutting machine assembly frame (21). Thereafter, the analog quantity acquisition card (51) controls the lens driving module to drive the distance between the objective lens (31) and the lens group (3) to adjust the laser focal length.

3. The laser cutting device for automatically correcting the unevenness of the wafer surface according to claim 2, characterized in that: The electromagnet (411) is electrically connected to the analog quantity acquisition card (51), and the analog quantity acquisition card (51) is used to independently energize the electromagnet (411) located near the gear (42).

4. The laser cutting device for automatically correcting the unevenness of the wafer surface according to claim 2, characterized in that: Each of the electromagnets (411) is provided with a filter (412), and the frequency band of electric energy output by each of the filters (412) is different from the frequency bands of electric energy output by all the other filters (412), so that each of the electromagnets (411) can only receive electric energy of a corresponding frequency band, and the analog quantity acquisition card (51) is connected to all of the filters (412) in parallel by electrical signals, so that the analog quantity acquisition card (51) can combine and output the electric energy of different frequency bands transmitted to each of the electromagnets (411).

5. The laser cutting device for automatically correcting the unevenness of the wafer surface according to claim 2, characterized in that: The rack (41) is provided with a frequency divider (413) connected to the electrical signal of each electromagnet (411); the frequency divider (413) outputs different frequency bands of electrical energy to each electromagnet (411); the frequency divider (413) is connected to the electrical signal of the analog quantity acquisition card (51) so that the analog quantity acquisition card (51) can combine the electrical energy of different frequency bands supplied to each electromagnet (411) and output them to the frequency divider (413).

6. The laser cutting device for automatically correcting the unevenness of the wafer surface according to claim 1, characterized in that: The lens group (3) is provided with a slide rail (43), the slide rail (43) is fixedly arranged, and the objective lens (31) is provided with a slider (44) which slides on the slide rail (43).

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