Wafer laser processing method and system

Abstract

The invention discloses a wafer laser processing method and system. In the grooving equipment, after a wafer is coated with laser cutting protection glue, an ultraviolet laser is matched with a machining platform, a metal layer on the front face of the wafer is cut and grooved, and the grooved wafer is cleaned and put back to be clamped; in the hidden cutting equipment, a wafer is inversely buckled on a working platform deck, an infrared laser is matched with the working platform deck, infrared light penetrates through a through cutting film to carry out hidden cutting on the wafer, and cracks are formed in the wafer on the path through which laser passes; in the film expanding machine, the through cutting film expands to decompose the wafer into crystal grains along cracks in the wafer. According to the invention, front slotting, back hidden cutting and film expanding processes are matched to complete cutting and separation of the wafer at one time, so that the production efficiency and the cutting quality are greatly improved. Through cooperation of the working platform deck and the ultrasonic cleaning device, the front face of the wafer is protected, and the front face of the wafer is prevented from being damaged during implicit cutting.

Description

Technical field:

[0001] The present invention belongs to the technical field of semiconductor wafer production, and in particular relates to a wafer laser processing method and system. Background technology:

[0002] In the semiconductor chip manufacturing process, wafer cutting is one of the important processes in the packaging and testing stage. In the commonly used chip structure, there is usually a metal layer on the surface of the chip on the silicon-based substrate. In order to facilitate cutting, the metal layer is usually removed before cutting. When using traditional cutting methods (such as wheel cutting) to remove the metal layer, the wheel cutting speed is slow and it is easy to cause film detachment, breakage, edge collapse, etc. The metal layer causes great damage to the wheel, increasing the consumption of the wheel. Laser has the characteristics of good consistency, concentrated energy, high degree of automation and convenience for large-scale production. In the field of wafer cutting, laser cutting has a trend of gradually replacing traditional cutting methods.

[0003] Laser cutting methods are mainly divided into two types: surface ablation cutting and invisible cutting. The laser for surface ablation cutting generally uses ultraviolet rays, which have low penetration. The depth that can be processed in a single time is small, only about 10μm at a time. Since the wafer has a certain thickness, the surface ablation cutting process takes a long time and has low processing efficiency. The laser for invisible cutting generally uses infrared rays. Although it has good penetration, it requires the processing surface to be flat. After the metal layer is removed from the surface of the wafer, the surface is rough and cannot be processed by invisible cutting.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention:

[0005] The object of the present invention is to provide a wafer laser processing method and system, which organically combines front grooving with back transparent film hidden cutting and film expansion, thereby overcoming the defects in the above-mentioned prior art.

[0006] To achieve the above-mentioned object, the present invention provides a wafer laser processing method, the steps of which are as follows: (1) in a slotting device, a robot takes out a wafer from a clamp of a loading station and sends it to a coating station, and the wafer is coated with a laser cutting protective glue at the coating station to form a protective film on the surface of the wafer;

[0007] (2) The robot delivers the wafer to the processing platform. The ultraviolet laser cooperates with the processing platform to melt the metal layer on the front of the wafer and open a cutting groove on the metal layer. After the groove is opened, the robot moves the wafer to the cleaning station to clean the laser cutting protective glue on the surface of the wafer and the dust left by the groove, and then puts the wafer back into the clamp;

[0008] (3) In the hidden cutting equipment, the robot places the wafer with the grooves on the front side upside down on the working stage. The wafer film connecting the wafer and the steel ring is a transparent film that can pass infrared rays. The infrared laser cooperates with the working stage to perform hidden cutting on the back side of the wafer. The infrared laser penetrates the transparent film and acts on the inside of the wafer, and cracks are formed inside the wafer along the path of the laser.

[0009] (4) After the laser hidden cutting is completed, the robot puts the wafer back into the clamp, and the ultrasonic cleaning device on the hidden cutting equipment is started to clean the work platform; the ultrasonic cleaning device generates ultrasonic waves from the positive pressure chamber, and the ultrasonic nozzle sprays the ultrasonic waves to the work platform. The ultrasonic waves clean the micron-sized particle dust remaining on the work platform, and the ultrasonic waves separate the dust from the surface of the work platform. The negative pressure chamber of the ultrasonic cleaning device simultaneously generates negative pressure, sucking the dust into the negative pressure chamber and discharging it; after the work platform is cleaned, the next wafer is hidden cut;

[0010] (5) In the film expansion machine, the wafer that has been grooved on the front and hidden cut on the back is placed on the lifting plate. The upper pressure plate covers the wafer and presses the steel ring. The lifting plate rises to push the wafer up. The wafer drives the through-cut film to push up. The through-cut film expands while it is pushed up. The tension of the through-cut film drives the wafer to decompose along the cracks inside the wafer to form grains. The lifting plate is reset, the upper pressure plate is opened, and the wafer after film expansion is taken out to complete the wafer cutting.

[0011] A wafer laser processing system, including slotting equipment, hidden cutting equipment, and film expander; the slotting equipment includes a loading station, a coating station, a cleaning station, a handling robot, an ultraviolet laser, and a processing platform, a coating station and a cleaning station are sequentially arranged on one side of the loading station, and the handling robot and the processing platform are both provided with power mechanisms, and the handling robot and the processing platform move in the X-axis direction and the Y-axis direction through the corresponding power mechanisms, and the movement trajectory of the handling robot in the X-axis direction passes through the loading station, the cleaning station and the coating station, and the movement trajectory of the handling robot in the Y-axis direction passes through the cleaning station, the coating station and the processing platform; the ultraviolet laser is located above the processing platform, and the processing platform cooperates with the ultraviolet laser; the hidden cutting equipment includes a loading workbench , loading and unloading robots, infrared lasers, work platforms, ultrasonic cleaning devices, and linear motion mechanisms. A loading and unloading robot is arranged between the loading work platform and the work platform. The infrared laser and the ultrasonic cleaning device are located above the work platform. The work platform is arranged on the linear motion mechanism, and the work platform is driven to move in the X-axis direction and the Y-axis direction by the linear motion mechanism. The work platform cooperates with the infrared laser; the film expanding machine includes a lifting plate, an upper pressure plate, a lifting mechanism, and a table top. A lifting plate is arranged on the table top, and the upper pressure plate can be opened and closed on the table top. The upper pressure plate is located above the lifting plate, and a lifting mechanism is arranged below the table top. The lifting mechanism is connected to the lifting plate, and the size of the lifting plate matches the size of the wafer, and the size of the upper pressure plate matches the size of the steel ring of the wafer.

[0012] Preferably, in the technical solution, the ultraviolet laser includes a limiting laser and a slotting laser. The limiting laser cooperates with the processing platform to form limiting slots on both sides of the edge of the metal layer on the front side of the wafer. The slotting laser cooperates with the processing platform to form a cutting slot on the metal layer on the front side of the wafer. The cutting slot is located between the limiting slots on both sides.

[0013] Preferably, in the technical solution, the wavelength of ultraviolet light emitted by the ultraviolet laser is 355 nm.

[0014] Preferably, in the technical solution, the wavelength of the infrared light emitted by the infrared laser is 900-1100 nm.

[0015] Preferably, in the technical solution, a layer of anti-reflection film is attached to the surface of the transparent film, the transparent film is made of PVC and PO composite material, and the anti-reflection film is made of PO material.

[0016] Preferably, in the technical solution, the work platform includes a metal base, an anti-stick coating, a ceramic suction cup, and a porous adsorption film. The surface of the metal base is provided with an anti-stick coating, the ceramic suction cup is provided on the metal base to form an adsorption area, the surface of the adsorption area is covered with a porous adsorption film, and the porous adsorption film is made of a polyethylene polymer porous film; the front side of the wafer is protected from damage by the porous adsorption film.

[0017] Preferably, in the technical solution, the ultrasonic cleaning device includes a positive pressure chamber, an ultrasonic nozzle, and a negative pressure chamber. The positive pressure chamber is connected to the positive pressure interface, the positive pressure interface is connected to the external positive pressure airway, an ultrasonic nozzle is arranged at the outlet of the positive pressure chamber, the negative pressure chamber is connected to the negative pressure interface, the negative pressure interface is connected to the negative pressure generator, the negative pressure chamber is located on both sides of the ultrasonic nozzle, and the ultrasonic nozzle and the inlet of the negative pressure chamber are arranged toward the surface of the working platform; positive pressure gas is blown through the positive pressure chamber to form an ultrasonic wave, and the ultrasonic wave is transmitted to the surface of the working platform by the ultrasonic nozzle.

[0018] Preferably, in the technical solution, the positive pressure chamber includes a chamber and a cavity, the chambers are connected by the cavity to form a continuous airflow channel, the chamber volume is larger than the cavity volume, the previous chamber and the subsequent cavity form an amplification and excitation unit, a plurality of continuous amplification and excitation units are formed in the airflow channel, and an ultrasonic nozzle is provided at the outlet of the airflow channel; when the positive pressure gas passes through the amplification and excitation unit, the flow velocity increases sharply due to the rapid change in volume, and the positive pressure gas generates ultrasonic waves due to the excitation, and the ultrasonic waves are amplified by one level each time they pass through an amplification and excitation unit, and are ejected from the ultrasonic nozzle after multiple stages of amplification.

[0019] Preferably, in the technical solution, the ultrasonic frequency is 20khz-80khz.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The front grooving process is used to remove the metal layer on the surface of the wafer, and the back hidden cutting process is used to make hidden cuts on the back of the wafer to form cracks inside the wafer. The film expansion process is used to separate the wafer into grains. The front grooving, back hidden cutting and film expansion are combined to complete the wafer cutting and separation in one process, which greatly improves the production efficiency and cutting quality. The front of the wafer is protected by the cooperation of the working stage and the ultrasonic cleaning device to prevent the front of the wafer from being damaged during hidden cutting. Description of the drawings:

[0022] Figure 1 1a is a diagram of the wafer initial state, 1b is a diagram of the wafer front groove state, 1c is a diagram of the wafer back hidden cutting state, 1d is a diagram of the wafer before film expansion, and 1e is a diagram of the wafer after film expansion;

[0023] Figure 2 This is a schematic diagram of the structure of the slotting equipment of the present invention;

[0024] Figure 3 It is a schematic diagram of the structure of the hidden cutting device of the present invention;

[0025] Figure 4 It is a schematic diagram of the working platform structure of the present invention;

[0026] Figure 5 It is a transverse cross-sectional view of the ultrasonic cleaning device of the present invention;

[0027] Figure 6 It is a longitudinal cross-sectional view of the ultrasonic cleaning device of the present invention;

[0028] Figure 7 It is a structural schematic diagram of the film expanding machine of the present invention;

[0029] Figure 8 This is a schematic diagram of the film expanding machine of the present invention in an open state;

[0030] Fig. 9 This is a diagram showing the change in the wafer film expansion state of the present invention. Specific implementation method:

[0031] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0032] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0033] like Figure 1 As shown, a wafer laser processing method comprises the following steps: (1) in a slotting device, a robot takes out a wafer from a clamp at a loading station, such as Figure 1 As shown in a, the robot moves along the X-axis direction to send the wafer to the coating station, where the wafer is coated with laser cutting protective glue to form a protective film on the surface of the wafer;

[0034] (2) The robot moves along the Y-axis direction to send the wafer to the processing platform. The processing platform moves in the X-axis direction and the Y-axis direction. The edge of the metal layer in the wafer circuit layer on the front side of the wafer is aligned with the limiting laser. The quasi-limiting laser is started to emit 355nm ultraviolet light. With the coordinated movement of the processing platform, the quasi-limiting laser cuts the edge of one side of the metal layer to form a limiting groove, and then cuts the edge of the other side of the metal layer to form a second limiting groove. With the coordinated movement of the processing platform, the slotting laser is aligned with the metal layer. The slotting laser is started to emit 355nm ultraviolet light to cut the metal layer on the front side of the wafer, remove the metal layer, and form a cutting groove in the metal layer. The depth of the cutting groove reaches the silicon substrate below the wafer circuit layer. Figure 1 As shown in b; after the slotting is completed, the robot removes the wafer from the processing platform and moves it to the cleaning station, cleans the laser cutting protective glue on the surface of the wafer and the dust left by the slotting, and then puts the wafer back into the clamp;

[0035] (3) In the hidden cutting equipment, the robot places the wafer with the front grooved upside down on the working stage. The front of the wafer is adsorbed on the porous adsorption film. The wafer film connecting the wafer and the steel ring is a transparent film that can pass infrared rays. The working stage moves in the X-axis direction and the Y-axis direction. The infrared laser is aimed at the back of the wafer. The infrared laser starts to output 1064nm infrared light. With the cooperation of the working stage, the infrared light cuts the back of the wafer in the X-axis direction and the Y-axis direction. The infrared light penetrates the anti-reflection film and the transparent film in turn and enters the silicon substrate of the wafer. Under the action of the infrared light, cracks are formed inside the silicon substrate along the path of the infrared light, such as Figure 1 As shown in c;

[0036] (4) After the laser hidden cutting is completed, the robot puts the wafer back into the clamp, and the ultrasonic cleaning device on the hidden cutting equipment is started to clean the work platform; the positive pressure gas passes through multiple continuous amplification and excitation units in the positive pressure chamber, and the positive pressure gas generates ultrasonic waves due to the excitation. After multiple stages of amplification, the ultrasonic waves are sprayed toward the work platform by the ultrasonic nozzle. The ultrasonic waves clean the micron-sized particle dust remaining on the work platform, and the ultrasonic waves separate the dust from the surface of the work platform. At the same time, the negative pressure chamber of the ultrasonic cleaning device generates negative pressure, and the dust is sucked into the negative pressure chamber and discharged; after the work platform is cleaned, the next wafer is hidden cut;

[0037] (5) In the film expander, the wafer that has been grooved on the front and cut on the back is placed on a lifting plate. Figure 1As shown in FIG. 4 , the upper pressure plate covers the wafer and presses the steel ring, the lifting plate rises to push the wafer up, and the outer edge of the through-cut film is pressed by the steel ring. As the through-cut film is lifted upward by the lifting plate along with the wafer, the through-cut film as a whole begins to expand outward from the center. During the outward expansion of the through-cut film, the tension generated by the through-cut film drives the wafer to expand. During the expansion of the wafer from the original boundary 46 to the new boundary 47, the wafer circuit layer and the silicon substrate in the wafer decompose along the cracks inside the wafer to form grains 48, as shown in FIG. Figure 1 As shown in FIG. 5 , the lifting plate is reset, the upper pressure plate is opened, the wafer after film expansion is taken out, and the wafer cutting is completed.

[0038] A wafer laser processing system includes a slotting device 1, a hidden cutting device 2, and a film expander 3; Figure 2 As shown, the slotting equipment 1 includes a loading station 10, a coating station 11, a cleaning station 12, a handling robot 13, a limit laser 14, a slotting laser 15, and a processing platform 16. The coating station 11 and the cleaning station 12 are arranged on one side of the loading station 10 in sequence. The handling robot 13 and the processing platform 16 are both provided with power mechanisms. The handling robot 13 and the processing platform 16 move in the X-axis direction and the Y-axis direction through the corresponding power mechanisms. The movement trajectory of the handling robot 13 in the X-axis direction passes through the loading station 10, the cleaning station 12 and the coating station 11. The movement trajectory of the handling robot 13 in the Y-axis direction The moving track is located between the cleaning station 12 or the coating station 11 and the processing platform 16; the limiting laser 14 and the slotting laser 15 are located above the processing platform 16, and the processing platform 16 cooperates with the limiting laser 14 and the slotting laser 15; the wavelength of ultraviolet light emitted by the limiting laser 14 and the slotting laser 15 is 355nm; the limiting laser 14 cooperates with the processing platform 16 to form limiting grooves on both sides of the edges of the metal layer 41 in the wafer circuit layer 40 on the front side of the wafer 4, and the slotting laser 15 cooperates with the processing platform 16 to form a cutting groove 42 at the metal layer 41, and the cutting groove 42 is located between the limiting grooves on both sides.

[0039] like Figure 3 As shown, the hidden cutting device 2 includes a loading workbench 20, a loading and unloading manipulator 21, an infrared laser 22, a work platform 23, an ultrasonic cleaning device 24, and a linear motion mechanism 25. A loading and unloading manipulator 21 is arranged between the loading workbench 20 and the work platform 23. The infrared laser 22 and the ultrasonic cleaning device 24 are located above the work platform 23. The work platform 23 is arranged on the linear motion mechanism 25. The work platform 23 is driven to move in the X-axis direction and the Y-axis direction by the linear motion mechanism 25. The work platform 23 cooperates with the infrared laser 22; the infrared light wavelength emitted by the infrared laser 22 is 900-1100nm. Figure 1As shown in c, a layer of anti-reflection film is attached to the surface of the transparent film 44, and the transparent film 44 is made of PVC and PO composite material, and the anti-reflection film is made of PO material. Figure 4 As shown, the work platform 23 includes a metal base 230, an anti-stick coating 231, a ceramic suction cup 232, and a porous adsorption film 233. The surface of the metal base 230 is provided with an anti-stick coating 231, the ceramic suction cup 232 is arranged on the metal base 230 to form an adsorption area, and the surface of the adsorption area is covered with a porous adsorption film 233, and the porous adsorption film 233 is made of a polyethylene polymer porous film; the porous adsorption film 233 is used to protect the front side of the wafer 4 from damage.

[0040] like Figure 5-6 As shown, the ultrasonic cleaning device 24 includes a positive pressure chamber 240, an ultrasonic nozzle 241, and a negative pressure chamber 242. The positive pressure chamber 240 is connected to a positive pressure interface 243, and the positive pressure interface 243 is connected to an external positive pressure airway. An ultrasonic nozzle 241 is arranged at the outlet of the positive pressure chamber 240, and the negative pressure chamber 242 is connected to a negative pressure interface 244, and the negative pressure interface 244 is connected to a negative pressure generator. The negative pressure chamber 242 is located on both sides of the ultrasonic nozzle 241, and the ultrasonic nozzle 241 and the inlet of the negative pressure chamber 242 are arranged toward the surface of the working platform 23; the positive pressure chamber 240 includes a chamber 245, a cavity 246, and a cavity The chambers 245 are connected by the cavity 246 to form a continuous airflow channel. The volume of the chamber 245 is larger than that of the cavity 246. The previous chamber 245 and the next cavity 246 form an amplification and excitation unit. A plurality of continuous amplification and excitation units are formed in the airflow channel. An ultrasonic nozzle 241 is provided at the outlet of the airflow channel. The positive pressure gas passes through the amplification and excitation unit. Due to the rapid change in volume, the flow rate increases rapidly. The positive pressure gas generates ultrasonic waves due to the excitation. The ultrasonic waves are amplified by one level each time they pass through an amplification and excitation unit. After multiple levels of amplification, the ultrasonic waves are ejected by the ultrasonic nozzle 241. The ultrasonic frequency is 20khz-80khz. The front side of the wafer 4 is protected by the cooperation of the working platform 23 and the ultrasonic cleaning device 24 to prevent the front side of the wafer 4 from being damaged during hidden cutting.

[0041] like Figure 7-8 As shown, the film expander 3 includes a lifting plate 30, an upper pressure plate 31, a lifting mechanism 32, and a table 33. The lifting plate 30 is arranged on the table 33. The upper pressure plate 31 can be opened and closed on the table 33 by a cylinder 34 arranged on the table 33. The upper pressure plate 31 is located above the lifting plate 30. The lifting mechanism 32 is arranged below the table 33. The lifting mechanism 32 is connected to the lifting plate 30. The size of the lifting plate 30 matches the size of the wafer 4. The size of the upper pressure plate 31 matches the size of the steel ring 45 of the wafer 4. Fig. 9As shown, the lifting mechanism 32 is started to drive the lifting plate 30 to rise, and the outer edge of the cutting film 44 is pressed by the steel ring 45. During the process of the cutting film 44 being lifted upward by the lifting plate 30 along with the wafer 4, the cutting film 44 as a whole begins to expand. The tension generated by the cutting film 44 drives the wafer 4 to expand. During the expansion of the wafer 4, the wafer 4 decomposes along the cracks inside the wafer to form grains 48.

[0042] The front side grooving, back side hidden cutting and film expansion are combined to complete the wafer cutting and separation in one process, which greatly improves the production efficiency and cutting quality.

[0043] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A wafer laser processing method, comprising the following steps: (1) in a slotting device, a robot takes out a wafer from a clamp of a loading station and sends it to a coating station, where a laser cutting protective glue is coated on the wafer to form a protective film on the surface of the wafer; (2) The robot delivers the wafer to the processing platform. The ultraviolet laser cooperates with the processing platform to melt the metal layer on the front of the wafer and open a cutting groove on the metal layer. After the groove is opened, the robot moves the wafer to the cleaning station to clean the laser cutting protective glue on the surface of the wafer and the dust left by the groove, and then puts the wafer back into the clamp; (3) In the hidden cutting equipment, the robot places the wafer with the grooves on the front side upside down on the working stage. The wafer film connecting the wafer and the steel ring is a transparent film that can pass infrared rays. The infrared laser cooperates with the working stage to perform hidden cutting on the back side of the wafer. The infrared laser penetrates the transparent film and acts on the inside of the wafer, and cracks are formed inside the wafer along the path of the laser. (4) After the laser cutting is completed, the robot puts the wafer back into the clamp, and the ultrasonic cleaning device on the laser cutting equipment is started to clean the work platform; the ultrasonic cleaning device generates ultrasonic waves from the positive pressure chamber, and the ultrasonic nozzle sprays the ultrasonic waves toward the work platform. The ultrasonic waves clean the micron-sized particle dust remaining on the work platform, and the ultrasonic waves separate the dust from the surface of the work platform. At the same time, the negative pressure chamber of the ultrasonic cleaning device generates negative pressure, and the dust is sucked into the negative pressure chamber and discharged; After the work stage is cleaned, the next wafer is cut; (5) In the film expansion machine, the wafer that has been grooved on the front and hidden cut on the back is placed on the lifting plate. The upper pressure plate covers the wafer and presses the steel ring. The lifting plate rises to push the wafer up. The wafer drives the through-cut film to push up. The through-cut film expands while it is pushed up. The tension of the through-cut film drives the wafer to decompose along the cracks inside the wafer to form grains. The lifting plate is reset, the upper pressure plate is opened, and the wafer after film expansion is taken out to complete the wafer cutting.

2. A system using the wafer laser processing method according to claim 1, characterized in that: It includes slotting equipment, hidden cutting equipment, and film expanding machine; the slotting equipment includes a loading station, a coating station, a cleaning station, a handling robot, an ultraviolet laser, and a processing platform. A coating station and a cleaning station are arranged on one side of the loading station in sequence. The handling robot and the processing platform are both provided with power mechanisms. The handling robot and the processing platform move in the X-axis direction and the Y-axis direction through the corresponding power mechanisms. The movement trajectory of the handling robot in the X-axis direction passes through the loading station, the cleaning station and the coating station, and the movement trajectory of the handling robot in the Y-axis direction passes through the cleaning station, the coating station and the processing platform; the ultraviolet laser is located above the processing platform, and the processing platform cooperates with the ultraviolet laser; the hidden cutting equipment includes a loading workbench, a loading and unloading machine A manipulator, an infrared laser, a work platform, an ultrasonic cleaning device, and a linear motion mechanism. A loading and unloading manipulator is arranged between the loading work platform and the work platform. The infrared laser and the ultrasonic cleaning device are located above the work platform. The work platform is arranged on the linear motion mechanism. The work platform is driven to move in the X-axis direction and the Y-axis direction by the linear motion mechanism. The work platform cooperates with the infrared laser. The film expanding machine includes a lifting disk, an upper pressure plate, a lifting mechanism, and a table. A lifting disk is arranged on the table. The upper pressure plate can be opened and closed on the table. The upper pressure plate is located above the lifting disk. A lifting mechanism is arranged below the table. The lifting mechanism is connected to the lifting disk. The size of the lifting disk matches the size of the wafer, and the size of the upper pressure plate matches the size of the steel ring of the wafer.

3. The wafer laser processing system according to claim 2, characterized in that: The ultraviolet laser includes a limiting laser and a slotting laser. The limiting laser cooperates with the processing platform to form limiting slots on both sides of the edge of the metal layer on the front side of the wafer. The slotting laser cooperates with the processing platform to form a cutting slot on the metal layer on the front side of the wafer. The cutting slot is located between the limiting slots on both sides.

4. The wafer laser processing system according to claim 2, characterized in that: The wavelength of ultraviolet light emitted by the ultraviolet laser is 355nm.

5. The wafer laser processing system according to claim 2, characterized in that: The infrared light emitted by the infrared laser has a wavelength of 900-1100nm.

6. The wafer laser processing system according to claim 5, characterized in that: A layer of anti-reflection film is attached to the surface of the transparent cutting film. The transparent cutting film is made of PVC and PO composite materials, and the anti-reflection film is made of PO material.

7. The wafer laser processing system according to claim 2, characterized in that: The working platform includes a metal base, an anti-stick coating, a ceramic suction cup, and a porous adsorption film. The surface of the metal base is provided with an anti-stick coating, the ceramic suction cup is arranged on the metal base to form an adsorption area, the surface of the adsorption area is covered with a porous adsorption film, and the porous adsorption film is made of a polyethylene polymer porous film.

8. The wafer laser processing system according to claim 2, characterized in that: The ultrasonic cleaning device includes a positive pressure chamber, an ultrasonic nozzle, and a negative pressure chamber. The positive pressure chamber is connected to a positive pressure interface, which is connected to an external positive pressure airway. An ultrasonic nozzle is arranged at the outlet of the positive pressure chamber. The negative pressure chamber is connected to a negative pressure interface, which is connected to a negative pressure generator. The negative pressure chamber is located on both sides of the ultrasonic nozzle, and the ultrasonic nozzle and the inlet of the negative pressure chamber are arranged toward the surface of the working platform.

9. The wafer laser processing system according to claim 8, characterized in that: The positive pressure chamber includes a chamber and a cavity. The chambers are connected by the cavity to form a continuous airflow channel. The volume of the chamber is larger than the volume of the cavity. The previous chamber and the subsequent cavity form an amplification and excitation unit. Multiple continuous amplification and excitation units are formed in the airflow channel. An ultrasonic nozzle is arranged at the outlet of the airflow channel. When the positive pressure gas passes through the amplification and excitation unit, the flow velocity increases sharply due to the rapid change in volume. The positive pressure gas generates ultrasonic waves due to the excitation. The ultrasonic waves are amplified by one level each time they pass through an amplification and excitation unit. After multiple levels of amplification, the ultrasonic waves are ejected from the ultrasonic nozzle.

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