Laser scribing device and laser scribing method

Abstract

The invention discloses a laser scribing device and a laser scribing method.The laser scribing device is used for conducting laser scribing on a substrate of a thin-film solar cell and comprises a movable scribing module and a control module, and the movable scribing module comprises a laser emitting unit, a reflector, a reflector driving unit and a range finder. And the reflecting mirror is used for reflecting the laser from the laser emitting unit and enabling the reflected laser to be vertically emitted to the processing surface of the substrate. The reflector driving unit is used for driving the reflector to move in the current scribing direction, and the focus position of the laser is adjusted by adjusting the position of the reflector in the current scribing direction. The range finder is used for measuring the distance of the current to-be-scribed position of the machined surface to obtain a distance value. And the control module is used for controlling the reflector driving unit to adjust the position of the reflector in the current scribing direction according to the distance value of the current to-be-scribed position. The structure for adjusting the laser focus is simple, and the cost of the scribing device can be reduced.

Description

Technical Field

[0001] The present application relates to the field of solar cells, and in particular to a laser scribing device and a laser scribing method. Background Art

[0002] When producing perovskite solar cells (PSCs), laser scribing is required to divide a large cell into several sub-cells. During processing, the focal point of the laser has a certain depth range (i.e., focal depth size), within which the processing effect can be consistent. Once this range is exceeded, the product will have a poor processing effect. Therefore, during laser processing, the relative position of the focus and the glass substrate must be maintained at all times. Due to the large area of ​​the substrate glass of the battery, the substrate glass itself will have a certain degree of curvature, and sometimes the curvature will exceed the depth range of the laser focus, i.e., defocus. In order to solve the problem of substrate glass bending, the industry usually uses a highly adjustable mechanical structure to correct the glass flatness through a multi-point support solution. However, this solution has high requirements for structural design accuracy, resulting in increased equipment costs. Moreover, each device must be adjusted, and maintenance and correction are required at intervals, which is time-consuming and labor-intensive. In addition, if the edge of the glass plate is warped, correction cannot be achieved.

[0003] Perovskite cells require three laser scribings before and after (the lines drawn are P1, P2 and P3 respectively). The parallelism between the three laser-drawn lines has very high precision requirements, and the industry usually requires ≤15um. The current solution is to use a camera to locate the two ends of P1 before the second scribing, and then perform the second scribing mechanically or by motor interpolation. Before the third scribing, the same method is used to locate the two ends of P2, and then perform the third scribing. The disadvantage of this is that the parallelism among the three lines cannot be guaranteed, and the precision is uncontrollable. At the same time, multiple positioning has a great impact on production efficiency. Summary of the invention

[0004] The purpose of the present application is to provide a laser scribing device and a laser scribing method, which can scribing the substrate glass of solar cells with different curvatures.

[0005] In order to achieve the above-mentioned purpose, the present application provides a laser scribing device for laser scribing a substrate of a thin-film solar cell, comprising a mobile scribing module and a control module, wherein the mobile scribing module comprises a laser emitting unit, a reflector, a reflector driving unit and a rangefinder; the reflector is used to reflect the laser from the laser emitting unit and make the reflected laser vertically emitted to the processing surface of the substrate; the reflector driving unit is used to drive the reflector to move in a current scribing direction, and adjust the focal position of the laser by adjusting the position of the reflector in the current scribing direction; the rangefinder is used to measure the distance of the current position to be scribed on the processing surface to obtain a distance value; the control module is used to control the reflector driving unit to adjust the position of the reflector in the current scribing direction according to the distance value of the current position to be scribed.

[0006] Optionally, the mobile scribing module also includes a high-speed camera, which is used to capture the position of the previous line that has been marked in real time and feed it back to the control module when marking the current position to be marked. The control module controls the relative movement of the mobile scribing module and the substrate according to the position information of the previous line, so as to adjust the distance between the laser processing point and the previous line in real time.

[0007] Optionally, the center of the field of view of the high-speed camera in the current marking direction is the processing point of the laser or is aligned with the processing point of the laser. When marking the current position to be marked, the high-speed camera captures the position of the previous line corresponding to the center of the field of view in real time and feeds back to the control module. The control module controls the relative movement of the mobile marking module and the substrate in real time based on the position of the previous line corresponding to the center of the field of view.

[0008] Optionally, the laser emitting unit includes a beam combining mirror and a light source, the beam combining mirror reflects the laser from the light source to the reflector; the high-speed camera and the reflector are arranged on opposite sides of the beam combining mirror, the shooting direction of the high-speed camera is the same as the direction of the laser reflected from the beam combining mirror to the reflector, the high-speed camera is used to capture the image of the beam combining mirror in real time to obtain the distance value between the previous line and the position opposite to the processing point and the processing point, and the control module uses the distance value to control the relative movement of the mobile scribing module and the substrate in real time.

[0009] Optionally, the mobile scribing module further comprises a driving motor, the driving motor is used to drive the movement of the beam combiner, and a closed-loop feedback control is performed between the high-speed camera and the driving motor. Optionally, closed-loop feedback control is performed between the rangefinder and the reflector drive unit.

[0010] In order to achieve the above object, the present application also provides a laser scribing method, which is implemented based on the above laser scribing device, and the method comprises the following steps: Controlling the relative movement of the mobile scribing module and the substrate so that the mobile scribing module corresponds to the current position to be scribed on the processing surface; Measuring the distance of the current position to be marked to obtain a current distance value; Controlling the reflector driving unit to adjust the position of the reflector in the current scribing direction according to the current distance value, so as to adjust the focal position of the laser; Control the mobile marking module to mark the current position to be marked in the current marking direction; Repeat the above steps.

[0011] Optionally, the controlling the mobile marking module to mark the current position to be marked in the marking direction includes: Real-time capture of the coordinates of the position where the previous line is aligned with the laser processing point; Based on the coordinates of the position where the previous line is aligned with the processing point of the laser, the relative movement of the mobile scribing module and the substrate is controlled in real time.

[0012] In the embodiment of the present application, the rangefinder measures the distance of the current position to be marked on the processing surface to obtain a distance value, and the control module controls the reflector drive unit to adjust the position of the reflector in the current marking direction according to the distance value of the current position to be marked, thereby achieving the purpose of adjusting the focal position of the laser. The structure of the focus adjustment of the present application is simple, which is conducive to reducing the cost of the marking device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the laser focal length adjustment according to an embodiment of the present application.

[0014] Figure 2 This is a principle block diagram of the scribing device of this application.

[0015] Figure 3 It is a schematic diagram of the three-dimensional structure of the scribing device of the present application.

[0016] Figure 4 This is a top view of the scribing device of the present application.

[0017] Figure 5 This is a schematic diagram of the process of adjusting the focal position of the laser in the scribing device of the present application.

[0018] Figure 6 Another schematic diagram of the process of adjusting the focal position of the laser in the scribing device of the present application. DETAILED DESCRIPTION

[0019] In order to explain the technical content, structural features, achieved objectives and effects of the present application in detail, the following is a detailed description in conjunction with the implementation methods and the accompanying drawings.

[0020] See also Figures 1 to 4 , after the laser is emitted from the laser light source for a certain distance, the light will converge at a point (just like a magnifying glass focuses the light), and this point is the focus F1 of the laser. In the figure, the laser is shot in from the left side, and is reflected onto the substrate B1 by the reflector 12. By adjusting the reflector 12 to move left and right, the focus F1 can be adjusted to fall behind the substrate B1 (point A), on the substrate B1 (point B), or in front of the substrate B1 (point C). It can be understood that the adjustment of the position of the reflector 12 can be ignored in actual operation and does not affect the actual marking. And because the glass of the substrate B1 itself has a certain degree of curvature, in actual operation, the glass of the substrate B1 may also bend to point C. At this time, the reflector 12 can be moved to the right so that the focus F1 falls on point C. The same is true for bending to point A, so it will not be repeated.

[0021] The present application discloses a laser scribing device for laser scribing a substrate B1 of a thin-film solar cell, comprising a mobile scribing module 1 and a control module 2, wherein the mobile scribing module 1 comprises a laser emitting unit 11, a reflector 12, a reflector driving unit 13, a rangefinder 14 and a control module 2; the reflector 12 is used to reflect the laser from the laser emitting unit 11 and to direct the reflected laser vertically toward a processing surface of the substrate B1; the reflector driving unit 13 is used to drive the reflector 12 to move in a current scribing direction, and to adjust the focal position of the laser by adjusting the position of the reflector 12 in the current scribing direction; the rangefinder 14 is used to measure the distance of a current position to be scribed on the processing surface to obtain a distance value; the control module 2 is used to control the reflector driving unit 13 to adjust the position of the reflector 12 in the current scribing direction according to the distance value of the current position to be scribed.

[0022] In the present application, "the reflected laser is vertically directed onto the processing surface of the substrate B1" means assuming that the processing surface is a complete plane, and setting the incident direction of the reflected laser to be perpendicular to the plane. The current position to be scribed is the linear area along the current scribing direction. When scribing, the mobile scribing module 1 of the scribing device moves to the position corresponding to the current position to be scribed after completing the scribing of the previous scribing position. The rangefinder 14, as a component of the mobile scribing module 1, also moves from the position corresponding to the previous scribing position to the position corresponding to the current scribing position to measure the distance corresponding to the current scribing position. In this way, the curvature of the substrate B1 can be fully considered, and the distance can be measured for each scribing position. Afterwards, the reflector drive unit 13 can be controlled to adjust the position of the reflector 12 in the scribing direction according to the distance value obtained by the distance measurement, so as to adjust to obtain a better laser focus position.

[0023] In the embodiment of the present application, the rangefinder 14 measures the distance of the current position to be marked on the processing surface to obtain a distance value, and the control module 2 controls the reflector drive unit 13 to adjust the position of the reflector 12 in the current marking direction according to the distance value of the current position to be marked, thereby achieving the purpose of adjusting the focal position of the laser. The structure of the present application for adjusting the focus is simple, which is conducive to reducing the cost of the marking device.

[0024] See also Figures 1 to 4 In some embodiments, if the distance value measured by the rangefinder 14 exceeds a preset range, the control module 2 adjusts the position of the reflector 12 in the marking direction by adjusting the reflector driving unit 13; if the distance value measured by the rangefinder 14 is within the preset range, the control module 2 notifies the rangefinder 14 to perform the next distance measurement.

[0025] See also Figures 1 to 4 In some embodiments, the mobile scribing module 1 further includes a high-speed camera 15, which is used to capture the position of the previous line that has been scribed in real time and feed it back to the control module 2 when scribing the current position to be scribed. The control module 2 controls the relative movement of the mobile scribing module 1 and the substrate B1 according to the position information of the previous line, so as to adjust the distance between the processing point of the laser and the previous line in real time. By means of the above-mentioned technical means of adjusting the distance between the processing point of the laser and the previous line in real time, the parallelism between the previous line and the current line to be scribed can be controlled at any position.

[0026] Optionally, the center of the field of view of the high-speed camera 15 in the current marking direction is the processing point of the laser or is aligned with the processing point of the laser. When marking the current position to be marked, the high-speed camera 15 captures the position of the center of the field of view corresponding to the previous line in real time and feeds it back to the control module 2. The control module 2 controls the relative movement of the mobile marking module 1 and the substrate B1 in real time based on the position of the center of the field of view corresponding to the previous line.

[0027] Specifically, the laser emitting unit 11 includes a beam combining mirror 111 and a light source 112. The beam combining mirror 111 reflects the laser from the light source 112 to the reflector 12. The high-speed camera 15 and the reflector 12 are arranged on opposite sides of the beam combining mirror 111. The shooting direction of the high-speed camera 15 is the same as the direction of the laser reflected from the beam combining mirror 111 to the reflector 12. The high-speed camera 15 is used to capture the image of the beam combining mirror 111 in real time to obtain the distance value between the previous line and the position opposite to the processing point and the processing point. The control module 2 uses the distance value to control the relative movement of the moving marking module 1 and the substrate B1 in real time.

[0028] More specifically, the mobile scribing module 1 further includes a driving motor 16 , which is used to drive the movement of the beam combiner 111 , thereby moving the position of the processing point, and closed-loop feedback control is performed between the high-speed camera 15 and the driving motor 16 .

[0029] Optionally, a focusing mirror 113 is further provided between the beam combining mirror 111 and the reflector 12. The beam combining mirror 111 reflects the laser from the light source 112 to the focusing mirror 113, and the focusing mirror 113 then focuses the laser onto the reflector 12. The driving motor 16 is used to drive the focusing mirror 113 and the beam combining mirror 111 to move simultaneously.

[0030] See also Figures 1 to 4 In some embodiments, closed-loop feedback control is performed between the rangefinder 14 and the reflector driving unit 13 .

[0031] See also Figures 1 to 5 The present application also discloses a laser scribing method, which is implemented based on the above-mentioned laser scribing device, and includes the following steps: S1, controlling the relative movement of the mobile scribing module 1 and the substrate B1, so that the mobile scribing module 1 corresponds to the current position to be scribed on the processing surface; S2, measuring the distance of the current position to be marked to obtain the current distance value; S3, controlling the reflector driving unit 13 to adjust the position of the reflector 12 in the current scribing direction according to the current distance value, so as to adjust the focal position of the laser; S4, controlling the mobile marking module 1 to mark the current position to be marked in the current marking direction; S5, repeat steps S1 to S4.

[0032] See also Figures 1 to 6 In some embodiments, controlling the mobile marking module 1 to mark the current position to be marked in the marking direction includes: S41, capturing the coordinates of the position where the previous line is aligned with the processing point of the laser in real time; S42, based on the coordinates of the position where the previous line is aligned with the processing point of the laser, the relative movement of the mobile scribing module 1 and the substrate B1 is controlled in real time.

[0033] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the patent scope of the present application are still within the scope covered by the present application.

Claims

1. A laser scribing device for laser scribing a substrate of a thin-film solar cell, characterized in that: The invention comprises a mobile scribing module and a control module, wherein the mobile scribing module comprises a laser emitting unit, a reflector, a reflector driving unit and a rangefinder; the reflector is used to reflect the laser from the laser emitting unit and make the reflected laser vertically irradiate the processing surface of the substrate; the reflector driving unit is used to drive the reflector to move in the current scribing direction, and adjust the focal position of the laser by adjusting the position of the reflector in the current scribing direction; the rangefinder is used to measure the distance of the current position to be scribed on the processing surface to obtain a distance value; The control module is used to control the reflector driving unit to adjust the position of the reflector in the current marking direction according to the distance value of the current position to be marked.

2. The laser scribing device according to claim 1, characterized in that: The mobile scribing module also includes a high-speed camera, which is used to capture the position of the previous line that has been marked in real time and feed it back to the control module when marking the current position to be marked. The control module controls the relative movement of the mobile scribing module and the substrate based on the position information of the previous line, so as to adjust the distance between the laser processing point and the previous line in real time.

3. The laser scribing device according to claim 2, characterized in that: The center of the field of view of the high-speed camera in the current marking direction is the processing point of the laser or is aligned with the processing point of the laser. When marking the current position to be marked, the high-speed camera captures the position of the previous line corresponding to the center of the field of view in real time and feeds back to the control module. The control module controls the relative movement of the mobile marking module and the substrate in real time based on the position of the previous line corresponding to the center of the field of view.

4. The laser scribing device according to claim 2, characterized in that: The laser emitting unit includes a beam combining mirror and a light source, and the beam combining mirror reflects the laser from the light source to the reflector; the high-speed camera and the reflector are arranged on opposite sides of the beam combining mirror, and the shooting direction of the high-speed camera is the same as the direction of the laser reflected from the beam combining mirror to the reflector. The high-speed camera is used to capture the image of the beam combining mirror in real time to obtain the distance value between the previous line and the position directly opposite to the processing point and the processing point, and the control module uses the distance value to control the relative movement of the mobile scribing module and the substrate in real time.

5. The laser scribing device according to claim 4, characterized in that: The mobile scribing module further includes a driving motor, and the driving motor is used to drive the movement of the beam combining mirror. Closed-loop feedback control is performed between the high-speed camera and the driving motor.

6. The laser scribing device according to claim 1, characterized in that: A closed-loop feedback control is performed between the rangefinder and the reflector driving unit.

7. A laser scribing method, characterized in that: The laser scribing method is implemented based on the laser scribing device according to any one of claims 1 to 6, and the method comprises the following steps: Controlling the relative movement of the mobile scribing module and the substrate so that the mobile scribing module corresponds to the current position to be scribed on the processing surface; Measuring the distance of the current position to be marked to obtain a current distance value; Controlling the reflector driving unit to adjust the position of the reflector in the current scribing direction according to the current distance value, so as to adjust the focal position of the laser; Control the mobile marking module to mark the current position to be marked in the current marking direction; Repeat the above steps.

8. The laser scribing method according to claim 7, characterized in that: The controlling the mobile marking module to mark the current position to be marked in the marking direction includes: Real-time capture of the coordinates of the position where the previous line is aligned with the laser processing point; Based on the coordinates of the position where the previous line is aligned with the processing point of the laser, the relative movement of the mobile scribing module and the substrate is controlled in real time.

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