Laser system, photovoltaic cell processing method, electronic device, and storage medium

Abstract

The application discloses a laser system, a photovoltaic cell processing method, an electronic device and a storage medium, and relates to the technical field of solar cells. The laser system can adjust the laser parameter of the laser, the position parameter of the lens group and the scanning parameter of the galvanometer in real time according to the monitoring result fed back by the monitoring module through the control module, so that the spot energy density, the spot size and the spot path can meet the process requirement of the photovoltaic cell patterning processing. Thus, the real-time optimization and adjustment of each parameter are performed, the corresponding relationship between the actual processing spot effect and each parameter is formed, the energy distribution of the modulated generated shaped spot is uniform, the relative stability of the spot size and the spot energy density in the processing process is ensured, the processing efficiency and the precision of the photovoltaic cell are improved, the laser system has flexibility and high efficiency to adapt to the process requirement of the patterning processing of different photovoltaic cells, and the time cost and the labor cost are effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a laser system, a photovoltaic cell processing method, an electronic device and a storage medium. BACKGROUND

[0002] Sustainable development is a global theme today. In order to replace the decreasing fossil energy, developing and utilizing renewable energy is one of the most direct and effective ways. With the continuous development of photovoltaic solar technology, the photoelectric conversion rate is continuously improved, and the industrial production cost is gradually reduced, so photovoltaic solar power generation is expected to become the mainstream of energy acquisition.

[0003] Among them, the patterning process has an important influence on the photoelectric conversion efficiency and service life of the solar cell, and laser is widely used in the process flow of various solar cells due to its high precision, high efficiency, low loss, low pollution and other characteristics. However, the laser system in the related art still has some problems in the application of the patterning process, including low processing efficiency, insufficient precision, and complex overall system debugging method, etc., which limits the flexibility and efficiency of the laser system, so that it cannot adapt to the process requirements of the patterning of photovoltaic cells of different sizes. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a laser system, a photovoltaic cell processing method, an electronic device and a storage medium, which can monitor the laser beam in real time to feedback and adjust the spot size, spot energy density and the like, thereby meeting the process requirements of the patterning of different photovoltaic cells.

[0005] In a first aspect, an embodiment of the present application provides a laser system, comprising:

[0006] A control module configured to control a laser to emit laser light according to laser parameters;

[0007] A laser electrically connected to the control module and configured to emit an initial light beam according to the laser parameters;

[0008] A diffraction element disposed behind the laser along an optical axis of the initial light beam and configured to modulate the initial light beam to form a modulated light beam;

[0009] A lens group electrically connected to the control module and disposed behind the diffraction element along an optical axis of the modulated light beam, and configured to adjust a spot size of the modulated light beam according to position parameters;

[0010] A beam splitter disposed behind the lens group along the optical axis of the modulated light beam and configured to divide the modulated light beam into a first light beam and a second light beam;

[0011] a monitoring module, electrically connected with the control module, arranged above the beam splitter along an optical axis of the first split beam, configured to receive the first split beam to monitor the modulated light beam, and send a monitoring result to the control module;

[0012] a galvanometer, electrically connected with the control module, arranged behind the beam splitter along an optical axis of the second split beam, configured to receive the second split beam, and adjust a scanning position, a scanning amplitude and a scanning speed of the second split beam according to a scanning parameter;

[0013] a field lens, fixedly connected with the galvanometer, configured to focus the second split beam to form a spot on a photovoltaic cell to be processed, so as to perform patterning processing;

[0014] The control module is further configured to adjust the laser parameter, the position parameter and the scanning parameter in real time according to the monitoring result, so that a spot energy density, a spot size and a spot path meet process requirements of the photovoltaic cell patterning.

[0015] In some embodiments of the present application, a reflective beam expander module is arranged between the laser and the diffraction element along an optical axis of the initial light beam, configured to adjust a beam parameter of the initial light beam;

[0016] The beam parameter includes a beam direction, a beam size and a divergence angle, and the reflective beam expander module includes:

[0017] a mirror, configured to adjust the beam direction;

[0018] a beam expander, configured to adjust the beam size and the divergence angle.

[0019] In some embodiments of the present application, the laser parameter includes at least one of a laser energy, a laser frequency, a laser power and a laser speed; and the initial light beam emitted according to the laser parameter is a Gaussian initial light beam with a normal distribution of beam energy.

[0020] In some embodiments of the present application, the diffraction element includes at least one of a grating, an aperture and a prism; and the diffraction element is configured to modulate a phase of the initial light beam to perform shaping to obtain the modulated light beam, and a spot shape of the modulated light beam includes a rectangle, a triangle, a circle or an ellipse.

[0021] In some embodiments of the present application, the lens group includes a first lens, a second lens and a third lens, and the position parameter includes a first interval and a second interval.

[0022] The second lens is arranged between the first lens and the third lens, the first lens and the second lens are apart from each other by the first distance, and the second lens and the third lens are apart from each other by the second distance.

[0023] The first lens, the second lens and the third lens are arranged on a coaxial motor, so that the control module adjusts the first distance and the second distance according to the position parameter to adjust the spot size.

[0024] In some embodiments of the present application, the monitoring module comprises an image sensor and a power meter; the monitoring result comprises a spot size and a spot energy density, the image sensor is used to monitor the spot size, and the power meter is used to monitor the spot energy density.

[0025] In some embodiments of the present application, the galvanometer is composed of a mirror group and a control motor; the mirror group is connected with the control motor, the scanning parameter comprises a mirror group angle, a motor swing amplitude and a motor rotation speed, the scanning position of the second light beam is controlled according to the mirror group angle, the scanning amplitude of the second light beam is controlled according to the motor swing amplitude, and the scanning speed of the second light beam is controlled according to the motor rotation speed.

[0026] In some embodiments of the present application, the laser parameter satisfies the following relationship:

[0027]

[0028]

[0029]

[0030] Wherein, E p is a single pulse energy, W is a laser power, f is a laser frequency, D is a spot diameter or side length, v is a laser speed, k is a unit area spot superposition coefficient, is a unit area spot energy density, A s is a spot area.

[0031] In some embodiments of the present application, the focal length of the first lens is a first focal length, the focal length of the second lens is a second focal length, and the focal length of the third lens is a third focal length; the spot size satisfies the following relationship:

[0032]

[0033]

[0034] Wherein, d ′ is a spot size, d is an initial spot size, fi f1 is a first focal length, f2 is a second focal length, f3 is a third focal length, L1 is a first distance, and L2 is a second distance.

[0035] In a second aspect, the embodiments of the present application further provide a photovoltaic cell processing method, applied to the laser system of the first aspect of the present application, comprising:

[0036] Obtaining process requirements of the photovoltaic cell; the process requirements include a target spot energy density, a target spot size and a target spot path of the patterning processing;

[0037] Modulating initial process parameters according to the process requirements; the initial process parameters include initial laser parameters, initial position parameters and initial scanning parameters, the initial laser parameters are used to adjust laser energy, laser frequency and laser power of the laser beam emitted by the laser system, the initial position parameters are used to adjust the spot size of the laser beam emitted by the laser system, and the initial scanning parameters are used to adjust the scanning position, scanning amplitude and scanning speed of the laser beam emitted by the laser system;

[0038] Adjusting the corresponding laser beam emitted by the laser according to the initial laser parameters, adjusting the position distance of the lens group to adjust the spot size of the laser beam according to the initial position parameters, adjusting the angle of the mirror group of the galvanometer, the swing amplitude of the motor and the rotation speed of the motor to adjust the scanning position, scanning amplitude and scanning speed of the laser beam according to the initial scanning parameters;

[0039] Obtaining the monitoring result of the monitoring module, and feeding back the adjustment of the initial laser parameters, the initial position parameters and the initial scanning parameters according to the monitoring result, until the corresponding laser beam of the monitoring result reaches the target spot energy density, the target spot size and the target spot path.

[0040] In a third aspect, the embodiments of the present application further provide an electronic device, comprising a memory and a processor, the memory stores a computer program, and the processor implements the photovoltaic cell processing method of the second aspect of the present application when executing the computer program.

[0041] In a fourth aspect, the embodiments of the present application further provide a computer readable storage medium, the storage medium stores a program, and the program is executed by a processor to implement the photovoltaic cell processing method of the second aspect of the present application.

[0042] The embodiments of the present application at least have the following beneficial effects:

[0043] The embodiment of the application provides a laser system, a photovoltaic cell processing method, an electronic device and a storage medium, wherein the laser system comprises a control module, which is used for controlling a laser to emit laser light according to laser parameters; the laser is electrically connected with the control module, and is used for emitting corresponding initial light beams according to the laser parameters; a diffraction element is arranged behind the laser along an optical axis of the initial light beams, and is used for modulating the initial light beams to form modulated light beams; a lens group is electrically connected with the control module, and is arranged behind the diffraction element along an optical axis of the modulated light beams, and is used for adjusting a spot size of the modulated light beams according to position parameters; a beam splitter is arranged behind the lens group along the optical axis of the modulated light beams, and is used for dividing the modulated light beams into first split light beams and second split light beams; a monitoring module is arranged above the beam splitter along the optical axis of the first split light beams, and is electrically connected with the control module, and is used for receiving the first split light beams to monitor the modulated light beams, obtaining monitoring results and sending the monitoring results to the control module; a galvanometer is arranged behind the beam splitter along the optical axis of the second split light beams, and is electrically connected with the control module, and is used for receiving the second split light beams, and adjusting a scanning position, a scanning amplitude and a scanning speed of the second split light beams according to scanning parameters; a field lens is fixedly connected with the galvanometer, and is used for focusing the second split light beams to form a spot on a photovoltaic cell to be processed, so as to perform patterning processing; the control module is further used for adjusting the laser parameters, the position parameters and the scanning parameters in real time according to the monitoring results, so that a spot energy density, a spot size and a spot path meet process requirements of the photovoltaic cell patterning, thereby improving processing efficiency and precision of the photovoltaic cell, and making the laser system have flexibility and high efficiency to adapt to process requirements of the photovoltaic cell patterning.

[0044] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and / or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0045] The above and / or additional aspects and advantages of the application will become apparent and be readily appreciated from the description of the embodiments, which follows, including the accompanying drawings.

[0046] Figure 1 FIG. 1 is a schematic diagram of a laser system according to an embodiment of the application;

[0047] Figure 2 FIG. 2 is a schematic diagram of a laser system according to another embodiment of the application;

[0048] Figure 3 FIG. 3 is a schematic diagram of a lens group according to an embodiment of the application;

[0049] Figure 4 FIG. 4 is a diagram of a parameter corresponding relationship according to an embodiment of the application;

[0050] Figure 5 FIG. 5 is a schematic diagram of a spot size according to an embodiment of the application;

[0051] Figure 6 is a parameter correspondence diagram provided by another embodiment of the present application;

[0052] Figure 7 is a flowchart of a photovoltaic cell processing method provided by an embodiment of the present application;

[0053] Figure 8 is a structural diagram of an electronic device provided by an embodiment of the present application.

[0054] The reference signs: control module 100, laser 200, diffraction element 300, lens group 400, first lens 401, second lens 402, third lens 403, beam splitter 500, monitoring module 600, galvanometer 700, field lens 800, material to be processed 900, reflection beam expander module 1000, first mirror 1001, second mirror 1003, third mirror 1004, beam expander 1002, electronic device 1100, processor 1101, memory 1102. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and cannot be used to limit the present application.

[0056] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0057] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as limiting the present application, which indicates or implies that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application.

[0058] In the description of the present application, the meaning of several is one or more, the meaning of multiple is more than two, greater than, less than, more than, etc. are understood as not including the number, above, below, etc. are understood as including the number. If it is described as first, second, it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0059] In the description of the present application, the words such as setting, installing, connecting and the like should be understood in a broad sense unless otherwise explicitly limited, and the skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0060] Sustainable development is a global theme today. In order to replace the decreasing fossil energy, developing and utilizing renewable energy is one of the most direct and effective ways. With the continuous development of photovoltaic solar technology, the photoelectric conversion rate is continuously improved, and the industrial production cost is gradually reduced, therefore, photovoltaic solar power generation is expected to become the mainstream of energy acquisition.

[0061] The emerging N-type silicon wafer TOPCON (Tunnel oxide passivated contact solar cell), HJT (Heterojunction solar cells), IBC (Interdigitated Back Contact) and other high-efficiency solar cells are constantly improving the industrialization scale with their higher photoelectric conversion rate and potential. Among them, the IBC type battery has the characteristics of no grid line on the front surface, positive and negative electrodes on the back surface, and spaced arrangement, so that sunlight can completely act on the surface of the battery without shading loss. Therefore, the efficiency of IBC type battery (26.2% of mass production photoelectric conversion rate, theoretical limit value 29.1%) is higher than that of TOPCON battery (25.4% of mass production photoelectric conversion rate, theoretical limit value 28.7%) and PERC battery (23.2% of mass production photoelectric conversion rate, theoretical limit 24.5%). The IBC type battery structure can be stacked with PERC, TOPCON, HJT, perovskite and other technologies, which is a new generation of platform technology. The stacking with TOPCON technology is called "TBC" battery, and the stacking with HJT technology is called "HBC" battery, so it is one of the most potential types of solar cells at present.

[0062] At present, in the preparation process of IBC type battery, in order to form two different doped regions in cross arrangement on the back surface of silicon wafer, patterning and alignment steps need to be introduced in the doping process and metallization process, and by setting different masks, different doped regions are isolated, and isolation layers are set between different doped regions. Therefore, the patterning process has an important influence on the subsequent other processes and even the photoelectric conversion efficiency and service life of the final solar cell. Laser is widely used in various solar cell process flows due to its high processing precision, high efficiency, low loss and small pollution, which is the main solution for IBC type battery patterning process.

[0063] In the process of processing IBC type solar cells and improved products of the same type, a laser is generally used to divide regions on the surface to form a pattern to complete patterning. The effect of the patterning process has a significant impact on subsequent etching, annealing and other processes. However, the laser system in the related art still has some problems in the application of the patterning process, including poor beam modulation performance of the laser 200, low processing efficiency, insufficient precision, and complex overall system debugging method, which limits the flexibility and efficiency of the laser system, and makes it unable to adapt to the process requirements of the patterning process of photovoltaic cells of different sizes. In order to promote the industrialization process of IBC type solar cells, a more perfect laser system and method are needed.

[0064] Based on this, the embodiment of the present application provides a laser system, a photovoltaic cell processing method, an electronic device and a storage medium, which can adjust the laser parameters, position parameters and scanning parameters in real time according to the monitoring results, so that the spot energy density, spot size and spot path can meet the process requirements of the patterning process of photovoltaic cells, thereby improving the processing efficiency and precision of photovoltaic cells, and making the laser system have flexibility and efficiency to adapt to the process requirements of the patterning process of different photovoltaic cells.

[0065] The laser system, photovoltaic cell processing method, electronic device and storage medium provided by the embodiment of the present application are specifically described by the following embodiments. First, the laser system in the embodiment of the present application is described.

[0066] Referring to Figure 1 The laser system of the embodiment of the present application includes:

[0067] The control module 100 controls the laser 200 to emit a laser beam according to the laser parameters.

[0068] The laser 200 is electrically connected with the control module 100, receives the control signal of the control module 100, and emits a corresponding initial beam according to the laser parameters in the control signal.

[0069] The diffraction element 300 is arranged behind the laser 200 along the optical axis of the initial beam, and performs beam shaping by adjusting the phase of the initial beam to modulate the initial beam to form a modulated beam.

[0070] The lens group 400 is arranged behind the diffraction element 300 along the optical axis of the modulated beam, and is electrically connected with the control module 100 to receive the control signal of the control module 100. The distance between the lenses is adjusted to adjust the spot size of the modulated beam according to the position parameters in the control signal.

[0071] A beam splitter 500 is disposed behind the lens group 400 along the optical axis of the modulated light beam, and divides the modulated light beam into a first sub-beam and a second sub-beam, wherein the first sub-beam is a reflected light beam and has a small portion of the energy in the modulated light beam, and the second sub-beam is a transmitted light beam and has a large portion of the energy in the modulated light beam;

[0072] A monitoring module 600 is electrically connected to the control module 100, and is disposed above the beam splitter 500 along the optical axis of the first sub-beam. The monitoring module 600 receives the first sub-beam to monitor the spot size and spot energy density of the modulated light beam, and obtains monitoring results and sends them to the control module 100.

[0073] A galvanometer 700 is disposed behind the beam splitter 500 along the optical axis of the second sub-beam. The galvanometer 700 receives the second sub-beam and is electrically connected to the control module 100. The galvanometer 700 receives control signals from the control module 100 and adjusts the scanning position, scanning amplitude and scanning speed of the second sub-beam according to the scanning parameters in the control signals.

[0074] A field lens 800 is fixedly connected to the galvanometer 700. The field lens 800 focuses the second sub-beam to form a spot on the material to be processed 900, such as a silicon wafer, to perform patterning processing.

[0075] Specifically, the control module 100 is further configured to adjust the laser parameters, position parameters and scanning parameters in real time according to the monitoring results fed back by the monitoring module 600, and then control the laser 200 to emit corresponding laser beams, control the distances between the lenses in the lens group 400 to adjust the spot size and spot energy density of the focused laser beams, and control the galvanometer 700 to adjust the spot path according to the adjusted scanning parameters, so that the final processed spot energy density, spot size and spot path meet the process requirements of the corresponding photovoltaic cell patterning processing.

[0076] It can be understood that, in the process of patterning the photovoltaic cell, the size of the spot energy density has an important influence on the processing quality and efficiency. When the spot energy density is too low, the laser beam cannot effectively heat the surface of the silicon wafer, thereby affecting the processing effect; when the spot energy density is too high, it will cause the surface of the silicon wafer to be excessively melted, resulting in unnecessary damage and deformation, thereby affecting the processing quality. Therefore, in order to achieve high-quality solar cell patterning processing, it is necessary to reasonably adjust the size of the spot energy density according to the specific situation.

[0077] On the other hand, the spot size is also an important parameter. The spot size determines the size of the focal point of the laser beam, and therefore directly affects the processing quality and efficiency. Specifically, a smaller spot size can improve the processing precision and resolution, but the processing speed will be slower; on the contrary, a larger spot size can improve the processing speed but the precision and resolution will be reduced.

[0078] Meanwhile, the spot path refers to the track left by the laser beam on the surface of the silicon wafer material. It can be understood that different photovoltaic cells have different process requirements for patterning, and the corresponding spot paths are also different. The present application controls and adjusts various parameters through real-time feedback, effectively improves the processing efficiency and precision of the photovoltaic cell, and makes the laser system flexible and efficient to adapt to the process requirements of different photovoltaic cells for patterning.

[0079] Referring to Figure 2 In some embodiments of the present application, the laser system further comprises:

[0080] The reflection beam expander module 1000 is arranged between the laser 200 and the diffractive element 300 along the optical axis of the initial light beam to adjust the beam parameters of the initial light beam; wherein the beam parameters include the beam direction, the beam size and the emission angle.

[0081] Specifically, the reflection beam expander module 1000 includes a mirror and a beam expander 1002, the mirror is used to adjust the beam direction, and the beam expander 1002 is used to adjust the beam size and the divergence angle. In some embodiments, the mirror can also include a first mirror 1001, a second mirror 1003 and a third mirror 1004, and the beam expander 1002 is arranged between the first mirror 1001 and the second mirror 1003 along the optical axis of the initial light beam. It can be understood that each mirror can adjust the angle position according to the light path to ensure that the initial light beam enters and exits at the correct angle and position when passing through each optical element of the laser system, reducing the aberration caused by the deviation of the light path. Those skilled in the art can set it according to actual needs, and this embodiment does not limit it.

[0082] In some embodiments, the initial light beam passes through the first mirror 1001 to adjust the beam direction, and then passes through the beam expander 1002 to further adjust the beam size and the divergence angle, so that the initial light beam meets the incident size requirement when entering the diffractive element 300, thereby ensuring that the shaped spot has uniform energy distribution and sharp and smooth edges. Specifically, the fixed magnification or adjustable magnification beam expander 1002 can be selected according to the size of the initial light beam. The beam expander 1002 can change the diameter of the light beam by changing the curvature of the lens to meet different incident size requirements, and can realize adjustable control of the light beam by adjusting its fixed magnification or replacing lenses with different magnifications. At the same time, the beam expander 1002 can also ensure that the shaped spot has uniform energy distribution, sharp and smooth edges, and avoid any processing quality problems. Therefore, the beam expander 1002 plays an important role in the laser processing process, and can realize fine adjustment of the beam diameter and power density by changing the lens parameters and magnification settings, to ensure the quality and efficiency of the entire processing process.

[0083] In some embodiments of the present application, the laser parameters include, but are not limited to, laser energy, laser frequency and laser power. Specifically, the laser energy refers to the total energy contained in a laser pulse, and for continuous laser, the laser energy is the energy delivered per second. The laser frequency refers to the number of cycles of vibration of the laser beam per unit time, usually measured in hertz (Hz). The laser frequency directly affects the color and spectral characteristics of the laser beam, for example, the frequencies of red and green lasers are different, so their wavelengths are also different. The laser power refers to the energy delivered by the laser beam per unit time. For continuous laser, the laser power is the energy delivered by the beam per second, usually measured in units of watts (W).

[0084] It can be understood that the laser energy is related to the laser wavelength, and according to Planck's formula, the energy carried by laser photons of different wavelengths is different. The shorter the laser wavelength, the greater the energy carried by a single photon, and therefore the greater the laser energy. In some embodiments, the laser 200 emits a Gaussian beam, and specifically, the initial beam emitted according to the laser parameters is a Gaussian initial beam with normally distributed beam energy. The Gaussian beam of the laser 200 has good beam quality, and the frequency power can be adjusted in a wide range, which can adapt to the needs of different patterning sizes. Specifically, short pulse, ultrashort pulse or continuous laser with a wavelength of 193 nm to 10600 nm can be selected, with an energy range of 1-1000 W and a frequency of 50 Hz-1 GHz. More preferably, a short pulse laser with a wavelength range of 193 nm to 1064 nm, a power of 10-2000 W and a frequency of 100-3000 kHz laser source. The present application does not limit this.

[0085] In some embodiments of the present application, the laser parameters are single pulse energy, laser frequency and laser speed, which satisfy the following relationships:

[0086]

[0087]

[0088]

[0089] wherein E p is the single pulse energy, W is the laser power, f is the laser frequency, D is the spot diameter or side length, v is the laser speed, k is the unit area spot overlap coefficient, is the unit area spot energy density, A s is the spot area.

[0090] Understandably, in the patterning process of IBC solar cells, after the laser removes the surface layer on the sample to form the mask pattern, a subsequent cleaning process is required. Therefore, the degree of damage caused by the laser processing determines the completeness of the patterning after cleaning, while the laser parameters determine the energy threshold acting on the surface of the IBC solar cell.

[0091] when When the value is within a certain range, the surface layer of the solar cell is removed without damage to the underlying layer, thus forming a mask pattern. IBC-type cell manufacturing typically involves multiple laser patterning and film cleaning processes to form a multi-layer structure. Different film layers require different energy thresholds. Therefore, under the condition of meeting the energy threshold, there are different combinations of single-pulse energy, laser frequency, and laser speed parameters. It is understood that the laser parameters also need to be selected and optimized based on the actual pattern size, processing efficiency, damage threshold, and processing accuracy; however, this application does not impose such limitations.

[0092] In some embodiments of this application, the diffraction element 300 is an optical device fabricated based on the principle of diffraction optics. By etching its surface or using a thin film structure, the phase of the light beam propagating through it is altered to create light spots of different shapes. The diffraction element 300 includes at least one of the following: a grating, an aperture, and a prism. The phase of the initial light beam is modulated and shaped by the diffraction element 300 to obtain a modulated light beam. The light spot has a uniform energy distribution, and the shape of the light spot includes, but is not limited to, rectangular, triangular, circular, or elliptical shapes. It is understood that those skilled in the art can configure it according to actual needs, and this embodiment does not impose any limitations on this.

[0093] In some embodiments of this application, the lens group 400 includes a first lens 401, a second lens 402, and a third lens 403, and the positional parameters of the lens group 400 include a first spacing and a second spacing. Specifically, refer to... Figure 3 The schematic diagram of lens group 400 shows a second lens 402 positioned between the first lens 401 and the third lens 403. The first lens 401 and the second lens 402 are separated by a first distance, and the second lens 402 and the third lens 403 are separated by a second distance. It can be understood that the first lens 401, the second lens 402, and the third lens 403 are mounted on a coaxial motor so that the control module 100 can adjust the first and second distances according to position parameters. After the modulated beam passes through the lens group 400, beam conversion is performed to magnify or reduce the beam spot size.

[0094] In some embodiments of this application, the focal length of the first lens 401 is a first focal length, the focal length of the second lens 402 is a second focal length, and the focal length of the third lens 403 is a third focal length.

[0095] Specifically, the spot size adjusted by the lens group 400 satisfies the following relationship:

[0096]

[0097]

[0098] wherein d ′ is the spot size, d is the initial spot size, f1 is the first focal length, f2 is the second focal length, f3 is the third focal length, L1 is the first distance, and L2 is the second distance.

[0099] Specifically, without the lens group 400, the customized diffractive element 300, and the field lens 800, the spot size obtained by the laser beam passing through the diffractive element 300 is the initial spot size d. In this embodiment, by adjusting the first distance between the first lens 401 and the second lens 402 and adjusting the second distance between the second lens 402 and the third lens 403, the final spot size d acting on the material to be processed 900 is changed ′ . Thus, by adjusting the position parameters of the control module 100, the spot size can be adjusted in real time, improving the flexibility and efficiency of the laser system.

[0100] In some embodiments of the present application, the monitoring module 600 includes an image sensor and a power meter, and the monitoring results include the spot size and the spot energy density. Specifically, the image sensor is used to monitor the spot size, and the power meter is used to monitor the spot energy density. Specifically, the image sensor can be a CCD camera, and the power meter is a tool for measuring the power and energy of the light beam, which can be used to measure the energy density of the laser spot, and is used to convert the optical signal into an electrical signal and process it. When measuring the spot energy density of the laser, a power density sensor can be used. This sensor usually uses a thermal sensor or a semiconductor material to measure the heat generated after the light beam is absorbed and converts it into an electrical signal. Since such a sensor is very sensitive to heat, it can accurately measure the energy density of the light beam. The monitoring module 600 monitors the quality of the debugging light beam in real time and feeds back the monitoring results to the control module 100 in real time, and forms a corresponding relationship between the spot size, the spot energy density and the laser parameters according to the light intensity distribution and the actual effect of the material surface, and provides basic data for parameter setting and optimization adjustment.

[0101] In some embodiments of this application, the galvanometer 700 consists of a reflector group and a control motor. Specifically, the reflector group includes two reflectors and is connected to the control motor. The scanning parameters include the reflector group angle, the motor swing amplitude, and the motor rotation speed. The scanning position of the second beam can be controlled according to the reflector group angle; a larger angle results in a farther scanning position, while a smaller angle results in a closer scanning position. Thus, by swinging the reflector group angle, the laser beam can scan a preset path to reach a preset position. The scanning amplitude of the second beam is controlled according to the motor swing amplitude; a larger swing amplitude results in a larger scanning range, while a smaller swing amplitude results in a smaller scanning range. The scanning speed of the second beam is controlled according to the motor rotation speed; a faster motor rotation speed results in a faster scanning speed, and a slower motor rotation speed results in a slower scanning speed. Therefore, the laser system can adjust the processing speed of the galvanometer 700 according to the scanning parameters through the control module 100, meeting different processing efficiency and accuracy requirements.

[0102] The following specific embodiment illustrates the application process of the laser system of this application. Specifically, a patterned processing test is performed on an IBC type battery with a diameter of 182*182mm, with a target processing line width of 200*1000μm.

[0103] The laser beam of the laser system is set to a focused spot size of 50*50μm, with a fixed frequency of 500kHz, a spot superposition coefficient k=1, and tangent spots. The control module 100 moves the first lens 401, the second lens 402, and the third lens 403 according to the parameter requirements, where the first focal length is 150mm, the second focal length is -10mm, and the third focal length is 50mm. Different position parameters correspond to different beam effects. The monitoring module 600 measures and feeds back to the control system to establish a corresponding relationship. When the relative position parameters of the lenses are a first spacing of 137.2mm and a second spacing of 4.28mm, the spot size reaches the ideal size. Under these beam conditions, controlling the laser parameters of the laser 200 yields a spot energy density process window range of approximately 0.0016-0.08μJ / μm. 2 Between these, a more preferred spot energy density is 0.048 μJ / μm. 2 . Reference Figure 4 As shown, the laser system obtains the following laser parameters through feedback adjustment: laser power 60W, laser frequency 500kHz, spot superposition coefficient k=1, motor rotation speed of galvanometer 700 25000mm / s, spot size and shape 50*50μm square, and position parameters of lens group 400 L1=137.2mm, L2=4.28mm.

[0104] When the process condition needs to be adjusted for optimization, to improve productivity and processing efficiency. Laser system according to the basic parameters, according to the need to set the ideal beam effect parameters in the laser system, usually keep the laser frequency and spot superposition coefficient unchanged. The required target spot size and target spot energy density are input into the control module 100, here the processing line width is preferred to be 100*100μm square, and the spot energy density is kept at 0.048μJ / μm 2 The initial beam is monitored by the monitoring module 600 at the beginning, the CCD camera measures the spot size parameter condition to be 50*50μm, and the lens group 400 position parameter remains unchanged, the monitoring result is obtained and fed back to the control module 100. The laser system detects that the output result does not match the set target spot size and target spot energy density, and thus adjusts.

[0105] First, adjust the lens group 400, change the spot size by changing the lens group 400 position parameter, when the first interval increases, the monitoring module 600 feeds back the real-time result to the control module 100, the spot size decreases with the increase of the first interval, the adjusted spot size is less than 50*50μm, that is, the adjustment direction makes the actual result and the target spot size difference increase, the laser system controls the lens group 400 to adjust in the opposite direction to reduce the first interval. In this way, the second interval is adjusted until the monitoring result of the spot size reaches the target spot size. At the same time, according to the actual spot size, the set energy density remains 0.048μJ / μm 2 unchanged. The monitoring module 600 feeds back the real-time laser power to the system, and the control module 100 calculates the actual spot energy density according to the formula, which can be subtracted from the target spot energy. When the result is negative, the system controls the laser 200 to increase the laser power, otherwise to decrease the laser power until the measured actual spot energy density is equal to the target spot energy density.

[0106] Further, refer to Figure 5 and Figure 6As shown, the actual processing line width 200*1000 μm is kept unchanged, and the laser frequency is fixed at 500 kHz. By changing the position parameters of the lens group 400, keeping the second lens 402 unchanged, adjusting the first distance to be 134.4 mm and the second distance to be 4.28 mm, the spot size reaches 100*100 μm, and the processing speed of the galvanometer 700 can be doubled to 50000 mm / s compared with 50*50 μm. Keeping the second lens 402 unchanged, adjusting the first distance to be 128.8 mm and the second distance to be 31.07 mm, the spot size reaches 200*200 μm, and the processing speed of the galvanometer 700 can be doubled to 100000 mm / s compared with 100*100 μm. According to the actual processing efficiency and size accuracy requirements, the laser parameters, position parameters and scanning parameters can be adjusted through the control module 100 of the laser system, so as to obtain the ideal spot size and stable unit area energy density

[0107] The laser system currently applied to the IBC type solar cell has fixed processing spot size and single pulse energy. When the process requirements change, important devices such as the laser 200 or the shaping element in the optical path system need to be replaced, the adjustment mode is complex, the time and labor cost is large, and the patterning accuracy is low. The laser system provided in the present application can flexibly adjust the spot size to adapt to the optimization and adjustment of the IBC type photovoltaic cell process, and according to the processing efficiency and patterning size requirements and the results of the previous process parameters, the main laser parameter test range is given to quickly find the process window.

[0108] The laser system can thus optimize and adjust each parameter to form a corresponding relationship between the actual processing spot effect and each parameter. The control module 100 adjusts the laser parameters, position parameters and scanning parameters in real time according to the monitoring results, so that the spot energy density, spot size and spot path meet the process requirements of the photovoltaic cell patterning process, the energy distribution of the shaped spot generated by the optical path modulation is uniform, the spot size can realize linear change of 10 μm to 1000 μm, the relative stability of the spot size and spot energy density in the processing process is ensured, the processing efficiency and accuracy of the photovoltaic cell are improved, the laser system has flexibility and high efficiency to adapt to the process requirements of the patterning process of different photovoltaic cells, and the time cost and labor cost are effectively reduced.

[0109] The embodiment of the present application also provides a photovoltaic cell processing method applied to a laser system, which is shown in Figure 7 The photovoltaic cell processing method includes but is not limited to the following steps S100 to S400.

[0110] Step S100, obtaining process requirements of a photovoltaic cell; the process requirements include target spot energy density, target spot size and target spot path of the patterning process;

[0111] In step S200, initial process parameters are modulated according to process requirements. The initial process parameters include initial laser parameters, initial position parameters and initial scanning parameters. The initial laser parameters are used to adjust laser energy, laser frequency and laser power of the laser beam emitted by the laser system. The initial position parameters are used to adjust the spot size of the laser beam emitted by the laser system. The initial scanning parameters are used to adjust the scanning position, scanning amplitude and scanning speed of the laser beam emitted by the laser system.

[0112] In step S300, the laser 200 emits a corresponding laser beam according to the initial laser parameters. The lens group 400 adjusts the position interval according to the initial position parameters to adjust the spot size of the laser beam. The mirror group of the galvanometer 700 adjusts the angle, motor swing amplitude and motor rotation speed according to the initial scanning parameters to adjust the scanning position, scanning amplitude and scanning speed of the laser beam.

[0113] In step S400, the monitoring result of the monitoring module 600 is obtained. The initial laser parameters, the initial position parameters and the initial scanning parameters are adjusted according to the monitoring result until the laser beam corresponding to the monitoring result reaches the target spot energy density, the target spot size and the target spot path.

[0114] The photovoltaic cell processing method of the embodiment is applied to the laser system as described above. For example, the control module in the laser system can execute the photovoltaic cell processing method including steps S100-S400 when running the computer program. The related description of the photovoltaic cell processing method is referred to the laser system as described above, and will not be repeated here.

[0115] Figure 8 The electronic device 1100 provided by the embodiment of the present application is shown. The electronic device 1100 includes a processor 1101, a memory 1102, and a computer program stored in the memory 1102 and executable on the processor 1101. The computer program is used to execute the photovoltaic cell processing method as described above when running.

[0116] The processor 1101 and the memory 1102 can be connected by a bus or other means.

[0117] The memory 1102 is a non-transitory computer readable storage medium, which can be used to store non-transitory software programs and non-transitory computer executable programs, such as the photovoltaic cell processing method described in the embodiment of the present application. The processor 1101 runs the non-transitory software programs and instructions stored in the memory 1102, thereby realizing the photovoltaic cell processing method as described above.

[0118] The memory 1102 can include a program storage area and a data storage area, where the program storage area can store an operating system, at least one application program required by a function, and the data storage area can store the photovoltaic cell processing method described above. In addition, the memory 1102 can include a high-speed random access memory 1102, and can also include a non-transitory memory 1102, such as at least one storage device, a flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory 1102 can optionally include a memory 1102 that is remotely located with respect to the processor 1101, and these remote memories 1102 can be connected to the electronic device 1100 through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0119] The non-transitory software programs and instructions required to implement the photovoltaic cell processing method described above are stored in the memory 1102, and when executed by one or more processors 1101, the photovoltaic cell processing method described above is performed, for example, the method steps S100 to S400 in the above-mentioned method are performed. Figure 7

[0120] The embodiments of the present application also provide a storage medium, which is a computer readable storage medium, and the storage medium stores a computer program. When the computer program is executed by a processor, the photovoltaic cell processing method described above is implemented. The memory, as a non-transitory computer readable storage medium, can be used to store non-transitory software programs and non-transitory computer executable programs. In addition, the memory can include a high-speed random access memory, and can also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory can optionally include a memory that is remotely located with respect to the processor, and these remote memories can be connected to the processor through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0121] The laser system, the photovoltaic cell processing method, the electronic device, and the storage medium provided by the embodiments of the present application, wherein the laser system adjusts the laser parameters, the position parameters, and the scanning parameters in real time according to the monitoring results through the control module, so that the spot energy density, the spot size, and the spot path meet the process requirements of the photovoltaic cell patterning processing. In this way, each parameter is optimized and adjusted, a corresponding relationship between the actual processing spot effect and each parameter is formed, the energy distribution of the shaped spot generated by the light path modulation is uniform, the relative stability of the spot size and the spot energy density in the processing process is ensured, the processing efficiency and the accuracy of the photovoltaic cell are improved, the laser system has flexibility and high efficiency to adapt to the process requirements of the patterning processing of different photovoltaic cells, and the time cost and the labor cost are effectively reduced.

[0122] ​The embodiments described above are only illustrative, and units described as separate components can or can not be physically separate, i.e., can be located in one place, or can be distributed over multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments.

[0123] Those of ordinary skill in the art will appreciate that all or some of the steps, systems, and methods described above can be embodied in software, firmware, hardware, and any suitable combination thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on computer-readable media, which can include computer storage media (or non-transitory media) and communication media (or transitory media). As is well known to those of ordinary skill in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, storage devices storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. Furthermore, it will be appreciated by those of ordinary skill in the art that communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and can include any information delivery media.

[0124] It should also be appreciated that various embodiments provided by the embodiments of the present application can be combined in any manner to achieve different technical effects. The above is a specific description of the preferred embodiments of the present application, but the present application is not limited to the above embodiments, and those skilled in the art can make various equivalent modifications or replacements without departing from the spirit of the present application.

Claims

1. A laser system, characterized in that, include: The control module is used to control the laser to emit laser light according to the laser parameters; A laser, electrically connected to the control module, is used to emit a corresponding initial beam according to the laser parameters; A diffraction element is disposed behind the laser along the optical axis of the initial beam to modulate the initial beam and form a modulated beam. The lens group, electrically connected to the control module, is positioned behind the diffraction element along the optical axis of the modulated beam, and is used to adjust the spot size of the modulated beam according to the position parameters. A beam splitter is disposed behind the lens group along the optical axis of the modulated beam, and is used to split the modulated beam into a first beam splitter and a second beam splitter. A monitoring module, electrically connected to the control module, is positioned above the beam splitter along the optical axis of the first beam splitter. It is used to receive the first beam splitter to monitor the modulated beam, obtain the monitoring results, and send them to the control module. A galvanometer, electrically connected to the control module, is positioned behind the beam splitter along the optical axis of the second beam splitter. It is used to receive the second beam splitter and adjust the scanning position, scanning amplitude, and scanning speed of the second beam splitter according to the scanning parameters. A field lens, fixedly connected to the galvanometer, is used to focus the second beam splitter to form a light spot onto the photovoltaic cell to be processed for patterning. The control module is also used to adjust the laser parameters, the position parameters and the scanning parameters in real time according to the monitoring results, so that the spot energy density, spot size and spot path meet the process requirements of the patterned processing of the photovoltaic cell; The lens group includes: a first lens, a second lens, and a third lens, and the position parameters include a first spacing and a second spacing; The second lens is disposed between the first lens and the third lens, the first lens and the second lens are separated by the first distance, and the second lens and the third lens are separated by the second distance; The first lens, the second lens, and the third lens are mounted on a coaxial motor so that the control module adjusts the first spacing and the second spacing according to the position parameters to adjust the light spot size. The first lens has a focal length of 1, the second lens has a focal length of 2, and the third lens has a focal length of 3; the spot size satisfies the following relationship: in, The size of the light spot. This is the initial spot size. The first focal length, For the second focal length, The third focal length, This is the first spacing. This is the second spacing.

2. The laser system according to claim 1, characterized in that, Also includes: A reflection beam expander module is positioned between the laser and the diffraction element along the optical axis of the initial beam, and is used to adjust the beam parameters of the initial beam. The beam parameters include beam direction, beam size, and divergence angle; the reflection beam expander module includes: A reflector is used to adjust the direction of the light beam; A beam expander is used to adjust the size of the beam and the divergence angle.

3. The laser system according to claim 1, characterized in that, The laser parameters include at least one of the following: laser energy, laser frequency, laser power, and laser speed; the initial beam emitted according to the laser parameters is a Gaussian initial beam with a normal energy distribution.

4. The laser system according to claim 1, characterized in that, The diffraction element includes at least one of the following: a grating, an aperture, and a prism; the diffraction element is used to modulate the phase of the initial beam to shape it to obtain the modulated beam, and the spot shape of the modulated beam includes: rectangular, triangular, circular, or elliptical.

5. The laser system according to claim 1, characterized in that, The monitoring module includes an image sensor and a power meter; the monitoring results include spot size and spot energy density, wherein the image sensor is used to monitor the spot size and the power meter is used to monitor the spot energy density.

6. The laser system according to claim 1, characterized in that, The galvanometer consists of a reflector group and a control motor; the reflector group is connected to the control motor, and the scanning parameters include the reflector group angle, the motor swing amplitude, and the motor rotation speed. The scanning position of the second beam is controlled according to the reflector group angle, the scanning amplitude of the second beam is controlled according to the motor swing amplitude, and the scanning speed of the second beam is controlled according to the motor rotation speed.

7. The laser system according to claim 3, characterized in that, The laser parameters satisfy the following relationship: in, For single-pulse energy, For laser power, The laser frequency, The diameter or side length of the light spot. For laser speed, The superposition coefficient of light spots per unit area. The energy density of the light spot per unit area. The area is the spot size.

8. A method for processing photovoltaic cells, characterized in that, The laser system applied to any one of claims 1 to 7 comprises: Obtain the process requirements for the photovoltaic cell; the process requirements include the target spot energy density, target spot size, and target spot path for patterned processing; The initial process parameters are modulated according to the process requirements. The initial process parameters include initial laser parameters, initial position parameters, and initial scanning parameters. The initial laser parameters are used to adjust the laser energy, laser frequency, and laser power of the laser beam emitted by the laser system. The initial position parameters are used to adjust the spot size of the laser beam emitted by the laser system. The initial scanning parameters are used to adjust the scanning position, scanning amplitude, and scanning speed of the laser beam emitted by the laser system. The laser emits a corresponding laser beam according to the initial laser parameters, the position spacing of the lens group is adjusted according to the initial position parameters to adjust the spot size of the laser beam, and the angle of the galvanometer's reflector group, the motor swing amplitude and the motor rotation speed are adjusted according to the initial scanning parameters to adjust the scanning position, scanning amplitude and scanning speed of the laser beam. The monitoring results of the monitoring module are obtained, and the initial laser parameters, the initial position parameters, and the initial scanning parameters are adjusted based on the feedback of the monitoring results until the laser beam corresponding to the monitoring results reaches the target spot energy density, the target spot size, and the target spot path.

9. An electronic device, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the photovoltaic cell processing method as described in claim 8.

10. A computer-readable storage medium, characterized in that, The storage medium stores a program, which is executed by a processor to implement the photovoltaic cell processing method as described in claim 8.

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