Laser-induced patterning device and method and photovoltaic cell

Abstract

The invention discloses laser-induced patterning equipment, a laser-induced patterning method and a photovoltaic cell. The laser-induced imaging equipment comprises a reaction tank, a light path system and a conveying platform, the reaction tank is used for accommodating an acid solution and is provided with a graphical station; the light path system can emit a set light beam to the graphical station; the conveying platform is arranged in the reaction tank and can enable the silicon sample to be located at the patterning station. The laser-induced patterning equipment provided by the invention is simple in structure, the process difficulty and the production cost are reduced, and the patterning precision of the photovoltaic cell can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic cell production and processing, and more specifically, to a laser-induced patterning device, method, and photovoltaic cell. Background Art

[0002] In the existing photovoltaic cell patterning process, process methods such as photoresist masking or screen printing are usually adopted. Among them, although the photoresist masking method can form relatively precise patterns, its process flow is complex, the equipment cost is high, and the process stability control requirements are relatively high. While the screen printing method has a relatively low equipment cost, its printing accuracy is poor and the repeatability is poor, which is not conducive to large-scale production. Summary of the Invention

[0003] An object of the present application is to provide a new technical solution for a laser-induced patterning device, method, and photovoltaic cell to at least solve one of the problems in the background art.

[0004] According to a first aspect of the present application, there is provided a laser-induced patterning device, including:

[0005] A reaction tank for containing an acid solution and provided with a patterning station;

[0006] An optical path system capable of emitting a set beam to the patterning station;

[0007] A conveying platform disposed in the reaction tank and capable of positioning a silicon sample at the patterning station.

[0008] Optionally, it further includes a cover plate made of acid-resistant and corrosion-resistant material and covering the mouth of the reaction tank.

[0009] Optionally, the acid-resistant and corrosion-resistant material includes one or more of polyethylene, polypropylene, polytetrafluoroethylene, fluorinated ethylene propylene, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, vinyl ester resin, and unsaturated polyester resin.

[0010] Optionally, a transparent window is provided on the cover plate corresponding to the patterning station, the transparent window is made of a transparent acid-resistant and corrosion-resistant material, and the set beam can pass through the transparent window and irradiate the patterning station.

[0011] Optionally, the reaction tank is further provided with a to-be-processed station, a retractable first baffle and a second baffle, and the conveying platform can position the silicon sample at the to-be-processed station and the patterning station;

[0012] Wherein, when the first baffle extends out, it can limit the silicon sample at the to-be-processed station, and when the first baffle retracts, it can allow the silicon sample to pass through;

[0013] When the second baffle extends, the silicon sample can be limited to the graphic processing position, and when the second baffle retracts, the silicon sample can pass through.

[0014] Optionally, the conveying platform includes a first power device and a plurality of rollers arranged side by side in a first direction, and the first power device is used to drive the plurality of rollers to roll so that the silicon sample can move along the first direction.

[0015] Optionally, it further includes a cleaning tank and a drying tank connected to the reaction tank in sequence. The cleaning tank is used to clean the silicon sample, and the drying tank is used to dry the silicon sample. The conveying platform extends to the cleaning tank and the drying tank so that the silicon sample can be located in the cleaning tank and the drying tank.

[0016] Optionally, an air inlet is provided on one side of the cleaning tank close to the reaction tank, and an air outlet is provided on one side of the reaction tank close to the cleaning tank, and the air inlet is communicated with the air outlet.

[0017] Optionally, the reaction tank, the cleaning tank and the drying tank are connected to form a single tank body, and partition plates are respectively arranged between the cleaning tank and the reaction tank and the drying tank to isolate different media in the tank body;

[0018] The tank body has an inclination angle of 0.1° to 10°, so that the cleaning tank is higher than the reaction tank.

[0019] Optionally, it further includes a second flow channel. The reaction tank, the cleaning tank, the drying tank and the conveying platform form a first flow channel, and the second flow channel has the same structure as the first flow channel and is arranged side by side;

[0020] The optical path system can emit a set beam to the graphic processing position of the first flow channel and can also emit a set beam to the graphic processing position of the second flow channel.

[0021] Optionally, it further includes a vision system, and the vision system can locate the silicon sample in the first flow channel and can also locate the silicon sample in the second flow channel.

[0022] Optionally, it further includes a second power device and a connecting rod connected to the second power device. The optical path system includes a laser emitter, and the vision system includes a first image acquisition device and a second image acquisition device;

[0023] The first image acquisition device and the second image acquisition device are respectively connected to both sides of the optical path system through the connecting rod, and the second power device is configured to be able to drive the connecting rod to move in a direction perpendicular to the first flow channel or the second flow channel;

[0024] Wherein, when the laser emitter is located above the patterning station of the first flow channel, the second image acquisition device can locate the silicon sample in the second flow channel;

[0025] When the laser emitter is located above the patterning station of the second flow channel, the first image acquisition device can locate the silicon sample in the first flow channel.

[0026] According to a second aspect of the present application, there is provided a laser-induced patterning method, which is applied to the patterning device described in the first aspect, and includes:

[0027] Placing the silicon sample in an acid solution and irradiating a set area of the silicon sample with a laser.

[0028] Optionally, the silicon sample includes one or more of single-crystalline silicon, polycrystalline silicon, doped polycrystalline silicon, amorphous silicon, doped amorphous silicon, silicon carbide, and doped silicon carbide.

[0029] Optionally, the acid solution is hydrofluoric acid with a concentration of 1% to 50 w%.

[0030] Optionally, the wavelength of the laser is 200 nm to 1130 nm.

[0031] Optionally, the power density of the laser is 0.001 W / cm 2 ~20 W / cm 2 .

[0032] Optionally, the laser is continuous light or pulsed light, and the spot shape of the laser is circular, elliptical, annular, rectangular, or strip-shaped.

[0033] According to a third aspect of the present application, there is provided a photovoltaic cell, including: processed by the laser-induced patterning device described in the first aspect; or, including:

[0034] Processed by the laser-induced patterning method described in the second aspect.

[0035] The laser-induced patterning device provided by the present application, by setting a reaction tank and an optical path system, when the silicon sample is placed in the patterning station with an acid solution, the optical path system can emit a set beam to the silicon sample in the patterning station, so as to achieve the purpose of selectively etching the laser-irradiated area of the silicon sample, reduce the process difficulty, improve the patterning accuracy of the silicon sample, and the device has a simple structure, is easy to operate, and reduces the production cost.

[0036] Through the following detailed description of the exemplary embodiments of the present application with reference to the accompanying drawings, other features and advantages of the present application will become clear. Description of the Drawings

[0037] The drawings incorporated in and forming a part of the specification illustrate embodiments of the present application and, together with the description thereof, are used to explain the principles of the present application.

[0038] Figure 1 It is a schematic structural diagram of a laser-induced patterning device provided by the present application.

[0039] Figure 2 is Figure 1 a top view of

[0040] Explanation of reference numerals in the drawings:

[0041] 1. Reaction tank; 2. Cleaning tank; 3. Drying tank; 4. Silicon wafer; 5. Roller; 6. Cover plate; 7. First baffle; 8. Second baffle; 9. Transparent window; 10. Laser emitter; 11. Air inlet; 12. Air outlet; 13. Partition board; 14. First image acquisition device; 15. Second image acquisition device; 16. Connecting rod;

[0042] 100. First flow channel; 200. Second flow channel. Detailed embodiments

[0043] Now, various exemplary embodiments of the present application will be described in detail with reference to the drawings. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application.

[0044] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way a limitation on the present application or its application or use.

[0045] Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies, methods, and devices should be considered as part of the specification.

[0046] In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0047] It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0048] As Figure 1As shown, according to the first aspect of the present application, a laser-induced patterning device is provided, which is applied to the production of photovoltaic cells and includes: a reaction tank 1, an optical path system, and a conveying platform. The reaction tank 1 is used to accommodate an acid solution and is provided with a patterning station; the optical path system can emit a set beam to the patterning station; the conveying platform is arranged in the reaction tank 1 and can place the silicon sample at the patterning station.

[0049] Specifically, in this embodiment, the provided laser-induced patterning device has a reaction tank 1 that can accommodate an acid solution. The setting of the optical path system can provide a set beam, so that when the silicon sample is located at the patterning station through the conveying platform, the set beam can perform laser irradiation on a specific area of the silicon sample, achieving the purpose of selectively etching the silicon sample (or film layer).

[0050] Among them, the set beam refers to that the characteristics of the laser beam such as wavelength, energy density, spot shape, laser type, irradiation time, power, etc. can be matched and designed according to the patterning requirements of the silicon sample to precisely control the etched area and depth, etc., and improve the accuracy of patterning. In addition, the higher the laser energy, the more it can accelerate the oxidation process of silicon, form SiO 2 react chemically with the acid solution to form a corrosion process of the laser-acid system, improving the processing efficiency of patterning.

[0051] In the above embodiment, the part of the reaction tank 1 in contact with the acid solution can be made of acid-resistant corrosion materials. The patterning station is arranged at a position where it can be in contact with the acid solution. Preferably, it is advisable to completely immerse the silicon sample in the acid solution to ensure the accuracy of the corrosion reaction.

[0052] The optical path system can adopt devices such as a laser emitter 10, etc., and can achieve the purpose of emitting a set beam according to actual production requirements, improving the applicability of the device. The optical path system can be arranged above the reaction tank 1 so that the set beam can irradiate the patterning station on the conveying platform.

[0053] The conveying platform can be a movable conveyor belt or other structures arranged in the reaction tank 1, or a support structure located at the patterning station, as long as it can ensure that the silicon sample can be located at the patterning station. Among them, the conveying platform can also be made of acid-resistant corrosion-resistant structures to improve the service life of the device. The laser-induced patterning device provided by the present application has a simple structure, reduces the process difficulty and production cost, and improves the accuracy of silicon sample patterning.

[0054] Optionally, as Figure 1 shown, the laser-induced patterning device further includes a cover plate 6. The cover plate 6 is made of acid-resistant corrosion materials and is covered on the mouth of the reaction tank 1.

[0055] Specifically, in practical applications, the optical path system is usually arranged above the reaction tank 1 so that the set beam can irradiate the silicon sample at the patterning station. The cover plate 6 made of acid-resistant corrosion material covered at the opening of the reaction tank 1 can isolate the optical path system from the acid solution, avoid the corrosion of the optical path system by the acid solution, and improve the service life of the patterning equipment.

[0056] Optionally, the acid-resistant corrosion material includes one or more of polyethylene, polypropylene, polytetrafluoroethylene, fluorinated ethylene propylene, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, vinyl ester resin, and unsaturated polyester resin. These materials can all achieve acid solution resistance, especially the corrosion resistance of hydrofluoric acid solution required for silicon sample patterning, and ensure the reliability of the isolation of the cover plate 6 from the acid solution and the optical path system.

[0057] Optionally, as Figure 1 shown, a transparent window 9 is provided on the cover plate 6 corresponding to the patterning station. The transparent window 9 is made of a transparent acid-resistant corrosion material, and the set beam can pass through the transparent window 9 and irradiate the patterning station. Among them, the transparent acid-resistant corrosion material can be made of materials such as ethylene-tetrafluoroethylene copolymer, etc., to ensure that the set beam can penetrate the transparent window 9, avoid interference of the cover plate 6 on the set beam, and further improve the accuracy of patterning processing.

[0058] Optionally, as Figure 1 shown, the reaction tank 1 is further provided with a to-be-processed station, a retractable first baffle 7, and a second baffle 8. The conveying platform can make the silicon sample located at the to-be-processed station and the patterning station; wherein, when the first baffle 7 extends out, the silicon sample can be limited at the to-be-processed station, and when the first baffle 7 retracts, the silicon sample can pass through; when the second baffle 8 extends out, the silicon sample can be limited at the patterning station, and when the second baffle 8 retracts, the silicon sample can pass through.

[0059] Specifically, in practical applications, the silicon sample can be sequentially conveyed to the patterning station through the conveying platform, that is, the silicon sample can be located at the to-be-processed station and wait before being conveyed to the patterning station. After the silicon sample at the patterning station is irradiated by the set beam to complete the patterning of the set pattern, the silicon sample located at the to-be-processed station is then conveyed to the to-be-patterned station for processing to improve the patterning efficiency. In some embodiments, the silicon sample located at the to-be-processed station can also react with the acid solution to remove unnecessary film layers and other structures on the surface to further improve the processing efficiency of the silicon sample.

[0060] In the above structure, when the first baffle 7 extends, it can keep the silicon sample at the processing station in this position. After the silicon sample on the patterning station is patterned, the first baffle 7 retracts, allowing the silicon sample at the processing station to pass through and be transported by the transport platform to the patterning station for further patterning. At the same time, the second baffle 8 extends to keep the silicon sample on the patterning station for processing. After patterning is completed, the second baffle 8 retracts, enabling the silicon sample to be transported to the designated position. The settings of the first baffle 7 and the second baffle 8 enable the transport platform to automatically transport the silicon sample to a specific position or limit it at a specific position through a simple mechanical structure, improving the process efficiency of the entire patterning process.

[0061] In the above embodiment, the first baffle 7 and the second baffle 8 can be arranged at the bottom of the reaction tank 1 or on the cover plate 6 at the opening of the reaction tank 1, and can be specifically designed according to actual requirements.

[0062] Optionally, as Figure 1 shown, the transport platform includes a first power device and a plurality of rollers 5 arranged side by side in the first direction. The first power device is used to drive the plurality of rollers 5 to roll, enabling the silicon sample to move in the first direction.

[0063] Specifically, in this embodiment, the transport platform is arranged as a plurality of rollers 5 arranged side by side in the first direction, so that when the first power device drives the plurality of rollers 5 to roll, the transport of the silicon sample can be realized. Among them, the first direction can be the direction from the processing station to the patterning station. The plurality of rollers 5 arranged side by side form a support plane, which can improve the stability during the transport of the silicon sample. Among them, the first power device can be realized by a device such as a motor, and the present application does not limit this.

[0064] Optionally, as Figure 1 shown, the laser-induced patterning device further includes a cleaning tank 2 and a drying tank 3 connected to the reaction tank 1 in sequence. The cleaning tank 2 is used to clean the silicon sample, and the drying tank 3 is used to dry the silicon sample. The transport platform extends to the cleaning tank 2 and the drying tank 3, enabling the silicon sample to be located in the cleaning tank 2 and the drying tank 3.

[0065] Specifically, in this embodiment, the patterning device further includes a cleaning tank 2 and a drying tank 3 to clean and dry the patterned sample, improving the patterning process efficiency of the silicon sample. The cleaning tank 2 can contain clean water or other cleaning liquids to clean the acid solution remaining in the reaction tank 1. A hair dryer or heating device is provided in the drying tank 3, so that the cleaned silicon sample can be dried in time. Among them, the transport platform can extend into the cleaning tank 2 and the drying tank 3 to facilitate the movement of the silicon sample, saving the power equipment required to separately transport the silicon sample into the cleaning tank 2 and the drying tank 3 and reducing the equipment cost.

[0066] Optionally, as Figure 1 shown, an air inlet 11 is provided on one side of the cleaning tank 2 close to the reaction tank 1, and an air outlet 12 is provided on one side of the reaction tank 1 close to the cleaning tank 2. The air inlet 11 is communicated with the air outlet 12.

[0067] Specifically, in this embodiment, the settings of the air inlet 11 and the air outlet 12 can cause a circulating exhaust air to be formed in the area between the reaction tank 1 and the cleaning tank 2, preventing the acid solution in the pickling tank from volatilizing into the cleaning tank 2, and improving the cleaning effect and the service life of the cleaning tank 2.

[0068] Optionally, as Figure 1 shown, the reaction tank 1, the cleaning tank 2 and the drying tank 3 are connected to form a single tank body. Partition plates 13 are respectively provided between the cleaning tank 2 and the reaction tank 1 and the drying tank 3 to isolate different media in the tank body; the tank body has an inclination angle of 0.1° to 10°, making the cleaning tank 2 higher than the reaction tank 1.

[0069] Specifically, in this embodiment, connecting the reaction tank 1, the cleaning tank 2 and the drying tank 3 to form a single tank body is convenient for the manufacture and installation of the equipment and can reduce the equipment cost. And setting the tank body to have an inclination angle of 0.1° to 10°, making the cleaning tank 2 higher than the reaction tank 1, can prevent the acid solution from flowing into the cleaning tank 2 and polluting the cleaning medium in the cleaning tank 2. In addition, the partition plates 13 respectively provided between the cleaning tank 2 and the reaction tank 1 and the drying tank 3 can isolate different media in the tank body, that is, isolate the cleaning tank 2 from the reaction tank 1 and the drying tank 3, avoiding the mutual pollution of the media in each tank, and improving the reliability of the functions of each tank and the quality of the patterned silicon sample.

[0070] Optionally, as Figure 1 and Figure 2 shown, the laser-induced patterning device further includes a second flow channel 200. The reaction tank 1, the cleaning tank 2, the drying tank 3 and the conveying platform form a first flow channel 100. The second flow channel 200 has the same structure as the first flow channel 100 and is arranged side by side; the optical path system can emit a set beam to the patterning position of the first flow channel 100 and can also emit a set beam to the patterning position of the second flow channel 200.

[0071] Specifically, in this embodiment, a second flow channel 200 is arranged side by side on one side of the first flow channel 100, so that the optical path system can alternately irradiate the silicon wafers 4 on the patterning stations in different flow channels, eliminating the need for a single flow channel to wait for the silicon wafers 4 to be transported in place, positioned, etc. When patterning is performed in the first flow channel 100, the silicon samples in the second flow channel 200 can be adjusted in place simultaneously, improving the patterning efficiency. At the same time, the optical path system is alternately transferred to the first flow channel 100 and the second flow channel 200 to emit a set beam to the patterning station, eliminating the need for the number of optical path systems provided and further reducing the equipment cost.

[0072] Optionally, as Figure 2 shown, the laser-induced patterning device further includes a vision system, and the vision system can locate the silicon samples in the first flow channel 100 and can also locate the silicon samples in the second flow channel 200.

[0073] Specifically, in the patterning device with a double flow channel, during the alternating processing of the optical path system, when it moves between the first flow channel 100 and the second flow channel 200, it is necessary to locate the silicon samples in the flow channel so that the set beam can be irradiated onto the set area of the silicon sample on the patterning station according to a predetermined scheme. The setting of the vision system can achieve the positioning of the silicon samples in the first flow channel 100 and the second flow channel 200, improving the accuracy of the set beam emitted by the optical path system for irradiating the silicon samples and ensuring the accuracy of silicon sample patterning. Among them, the vision system can be an image recognition device such as a camera, and the present application does not limit this.

[0074] Optionally, as Figure 2 shown, the patterning device further includes a second power device and a connecting rod 16 connected to the second power device. The optical path system includes a laser emitter 10, and the vision system includes a first image acquisition device 14 and a second image acquisition device 15; the first image acquisition device 14 and the second image acquisition device 15 are respectively connected to both sides of the optical path system through the connecting rod 16, and the second power device is configured to be able to drive the connecting rod 16 to move in a direction perpendicular to the first flow channel 100 or the second flow channel 200; wherein, when the laser emitter 10 is located above the patterning station of the first flow channel 100, the second image acquisition device 15 can locate the silicon samples in the second flow channel 200; when the laser emitter 10 is located above the patterning station of the second flow channel 200, the first image acquisition device 14 can locate the silicon samples in the first flow channel 100.

[0075] Specifically, in this embodiment, the laser emitter 10, the first image acquisition device 14, and the second image acquisition device 15 are connected together by the connecting rod 16, so that the second power device can drive the connecting rod 16 to move towards the direction of the first flow channel 100 or the second flow channel 200, so as to realize the positioning of the optical system and one of the two image sensors can be positioned to the flow channel without the optical system, so as to position the silicon sample in the corresponding flow channel. In practical applications, a control module may also be included, and the optical system, the vision system, and the second power device are all connected to the control module, so as to control the characteristics of the set light beam emitted by the optical system and the movement of the second power device by receiving the positioning result of the silicon sample by the vision system.

[0076] In the above embodiment, the optical path system may include optical components such as galvanometers. The first image acquisition device 14 and the second image acquisition device 15 may adopt CCD (Charge-Coupled Device), and the second power device may adopt devices such as motors.

[0077] According to the second aspect of the present application, a laser-induced patterning method is provided, which is applied to the patterning device of the first aspect. Refer to Figures 1 to 2 , including: placing the silicon sample in an acid solution and irradiating a set area of the silicon sample with a laser.

[0078] Specifically, the laser-induced patterning method provided in this embodiment can be implemented by using the laser-induced patterning device of the first aspect. That is, a hydrofluoric acid solution can be set in the reaction tank 1, the silicon sample is placed on the patterning position in the reaction tank 1, and the set area of the silicon sample is irradiated by the set light beam emitted by the optical system. Among them, the set area is the area that needs to be etched, and the set light beam can be irradiated on the set area through the control of the optical path system.

[0079] In the above embodiment, selective etching is formed by irradiating the silicon material in the HF solution with a laser. During this process, when the laser irradiates the silicon wafer, high-energy photons will be absorbed by the electrons in the silicon crystal, thereby exciting the electrons to jump from the valence band to the conduction band, generating a large number of electron-hole pairs. Among them, the higher the laser energy, the more photo-generated electron-hole pairs are generated. The high concentration of holes helps to accelerate the oxidation process of silicon to form SiO 2 layer. And HF acid is a strong acid, and it can react chemically with SiO 2 to form the laser-HF corrosion system of the present application. During the corrosion process, the anodic reaction is:

[0080] Si + 2h + + 2OH - + 6HF → H 2 ↑ + H 2 SiF6 +2H 2 O (1)

[0081] The cathode reaction is:

[0082] 2H + +2e - →H 2 ↑ (2)

[0083] The above process can precisely control the etching area and depth by controlling the power, irradiation time, and position of the laser. Compared with the HF-HNO 3 etching system in the prior art, the laser-induced patterning method provided in this application reduces the usage amount of chemical reagents, lowers the production cost and waste liquid treatment cost, reduces environmental pollution, and conforms to the development trend of green manufacturing.

[0084] In addition, the laser processing has high precision and can be used for patterning preparation, eliminating the preparation and removal of masks, reducing the process difficulty and manufacturing cost. At the same time, the laser has higher precision, stronger patterning flexibility, less damage to solar cell wafers, and high corrosion controllability, and can achieve nm-level corrosion depth control.

[0085] In the above embodiments, the silicon sample includes one or more of single-crystalline silicon, polycrystalline silicon, doped polycrystalline silicon, amorphous silicon, doped amorphous silicon, silicon carbide, and doped silicon carbide. The acid solution can be hydrofluoric acid with a concentration of 1% to 50 w%. The wavelength of the laser is 200 nm to 1130 nm. The power density of the laser is 0.001 W / cm 2 ~20 W / cm 2 . The laser type can be continuous light or pulsed light, and the laser spot shape is circular, elliptical, annular, rectangular, or strip-shaped. It is specifically designed according to actual needs, and this application does not limit it. Among them, the solution concentration range of hydrofluoric acid, the wavelength range of the laser, and the power density range can ensure the accuracy and efficiency of laser corrosion.

[0086] To make the technical effects of the laser-induced patterning method provided in this application clearer, the following provides Example 1 and Example 2 to specifically introduce the above method process.

[0087] Example 1:

[0088] In this example, a continuous laser is used to emit a set beam. The wavelength of the laser is 1064 nm, the full power is 1000 W, and the used spot is an 110 um square spot.

[0089] The processed silicon sample is a topcon process wafer, and its structure from top to bottom is, in sequence, the textured surface and p-doped layer, 140um n-type monocrystalline silicon substrate, 1.3nm tunneling oxide layer, 110nm n-poly, and 20nm psg.

[0090] The silicon sample is placed in a 30w% HF solution. At this time, the surface psg layer will be quickly etched away. The laser processing power is 500W, the scanning speed is 40m / s, and the corresponding power density is 4.13W / cm 2 .

[0091] Through the above process flow, the specified laser area of the silicon wafer 4 can be etched, reducing the thickness of the 110nm n-poly to 70nm, thereby forming a selective thinning. Among them, the laser area (set area) is a non-metal contact area. After the poly is thinned, it helps to improve the problem of parasitic absorption of the battery. The thickness is thinned by 40nm, and the corresponding current density is increased by 0.37mA / cm 2 , and finally the battery efficiency is increased by 0.23%.

[0092] Example 2:

[0093] In this example, a pulsed laser is used to emit a set beam, making the laser wavelength 532nm, the pulse width 30ns, the full power 100W, and the used light spot a 250um square light spot.

[0094] The processed silicon sample has a new battery structure, which from top to bottom is, in sequence: 20nm psg, 100nm n-poly, 1.3nm tunneling oxide layer, 140um n-type monocrystalline silicon substrate, 1.5nm tunneling oxide layer, 140nm p-poly, and 25nm bsg.

[0095] The silicon sample is placed in a 20w% HF solution. At this time, the surface bsg and psg layers will be quickly etched away. The laser processing power is 70W, the scanning speed is 20m / s, and the corresponding power density is 0.11W / cm 2 .

[0096] Through the above process flow, the specified laser area (set area) can be etched, completely etching away the non-metal area n-poly, thereby forming a poly-finger structure. This solution can realize the simplified preparation of the new battery structure.

[0097] It can be seen from Example 1 and Example 2 that the chemical reagents used in the laser-induced patterning method provided by this application are less, the processing difficulty is reduced, and the etching accuracy is higher. When applied to the existing photovoltaic cell production, it can reduce the production cost and improve the production quality.

[0098] According to a third aspect of the present application, a photovoltaic cell is provided, including: being processed by the laser-induced patterning device of the first aspect; or, including: being processed by the laser-induced patterning method of the second aspect.

[0099] Specifically, in this embodiment, the provided photovoltaic cell can be processed by the laser-induced patterning device provided in the first aspect of the present application. Its processing device has a simple structure and can ensure the accuracy of patterning, improving the yield rate of the photovoltaic cell. In addition, the photovoltaic cell provided in the present application can also be processed by the laser-induced patterning method provided in the second aspect of the present application. It uses fewer chemical reagents, reducing the waste liquid treatment cost and environmental pollution, and the processing difficulty is reduced with a higher patterning accuracy.

[0100] The photovoltaic cell provided in the present application has a lower manufacturing cost and processing difficulty, and can ensure the quality of the photovoltaic cell, realizing the high-quality and simplified preparation of the photovoltaic cell structure.

[0101] In the above embodiments, the differences between the embodiments are mainly described. As long as the different optimization features between the embodiments are not contradictory, they can be combined to form a better embodiment. Considering the brevity of the text, it will not be elaborated here.

[0102] Although some specific embodiments of the present application have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A laser induced patterning device, characterized in that: include: A reaction tank, the reaction tank is used to contain an acid solution and is provided with a patterning station; An optical path system, the optical path system can emit a set light beam to the patterning station; The conveying platform is arranged in the reaction tank and can place the silicon sample at the patterning station.

2. The laser induced patterning device according to claim 1, characterized in that: It also includes a cover plate, which is made of acid-resistant material and covers the notch of the reaction tank.

3. The laser induced patterning device according to claim 2, characterized in that: The acid-resistant material includes one or more of polyethylene, polypropylene, polytetrafluoroethylene, fluorinated ethylene propylene, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polychlorotrifluoroethylene, vinyl ester resin and unsaturated polyester resin.

4. The laser induced patterning device according to claim 2, characterized in that: A transparent window is arranged on the cover plate corresponding to the graphic processing station. The transparent window is made of transparent acid-resistant material. The setting light beam can pass through the transparent window and irradiate the graphic processing station.

5. The laser induced patterning device according to claim 1, characterized in that: The reaction tank is also provided with a processing station, a retractable first baffle and a second baffle, and the conveying platform can place the silicon sample at the processing station and the patterning station; Wherein, when the first baffle is extended, the silicon sample can be confined to the processing station, and when the first baffle is retracted, the silicon sample can be allowed to pass through; When the second baffle is extended, the silicon sample can be confined at the patterning station, and when the second baffle is retracted, the silicon sample can be allowed to pass through.

6. The laser induced patterning device according to claim 1, characterized in that: The conveying platform includes a first power device and a plurality of rollers arranged side by side along a first direction, wherein the first power device is used to drive the plurality of rollers to roll so that the silicon sample can move along the first direction.

7. The laser induced patterning device according to any one of claims 1 to 6, characterized in that: It also includes a cleaning tank and a drying tank connected to the reaction tank in sequence, the cleaning tank is used to clean the silicon sample, and the drying tank is used to dry the silicon sample. The conveying platform extends to the cleaning tank and the drying tank, so that the silicon sample can be located in the cleaning tank and the drying tank.

8. The laser induced patterning device according to claim 7, characterized in that: An air inlet is provided on one side of the cleaning tank close to the reaction tank, and an air outlet is provided on one side of the reaction tank close to the cleaning tank, and the air inlet is communicated with the air outlet.

9. The laser induced patterning device according to claim 7, characterized in that: The reaction tank, the cleaning tank and the drying tank are connected to each other to form a tank body, and isolation plates are respectively arranged between the cleaning tank, the reaction tank and the drying tank to isolate different media in the tank body; The tank body has an inclination angle of 0.1° to 10°, so that the cleaning tank is higher than the reaction tank.

10. The laser induced patterning device according to claim 7, characterized in that: It also includes a second flow channel, the reaction tank, the cleaning tank, the drying tank and the conveying platform form a first flow channel, and the second flow channel has the same structure as the first flow channel and is arranged side by side; The optical path system can emit a setting light beam to the patterning station of the first flow channel, and can emit a setting light beam to the patterning station of the second flow channel.

11. The laser induced patterning device according to claim 10, characterized in that: Also included is a vision system capable of locating the silicon sample within the first flow channel and capable of locating the silicon sample within the second flow channel.

12. The laser induced patterning device according to claim 11, characterized in that: It also includes a second power device and a connecting rod connected to the second power device, the optical path system includes a laser transmitter, and the visual system includes a first image acquisition device and a second image acquisition device; The first image acquisition device and the second image acquisition device are respectively connected to two sides of the optical path system through the connecting rod, and the second power device is configured to drive the connecting rod to move in a direction perpendicular to the first flow channel or the second flow channel; Wherein, when the laser emitter is located above the patterning station of the first flow channel, the second image acquisition device can locate the silicon sample in the second flow channel; When the laser emitter is located above the patterning station of the second flow channel, the first image acquisition device can locate the silicon sample in the first flow channel.

13. A laser induced patterning method, applied to the patterning device according to any one of claims 1 to 12, characterized in that: include: The silicon sample is placed in an acid solution and a laser is used to irradiate a set area of ​​the silicon sample.

14. The laser induced patterning method according to claim 13, characterized in that: The silicon sample includes one or more of single crystal silicon, polycrystalline silicon, doped polycrystalline silicon, amorphous silicon, doped amorphous silicon, silicon carbide and doped silicon carbide.

15. The laser induced patterning method according to claim 13, characterized in that: The acid solution uses hydrofluoric acid with a concentration of 1% to 50w%.

16. The laser induced patterning method according to claim 13, characterized in that: The wavelength of the laser is 200nm-1130nm.

17. The laser induced patterning method according to claim 13, characterized in that: The power density of the laser is 0.001 W / cm 2 ~20W / cm 2 .

18. The laser induced patterning method according to claim 13, characterized in that: The laser is continuous light or pulsed light, and the spot shape of the laser is circular, elliptical, ring-shaped, rectangular or strip-shaped.

19. A photovoltaic cell, characterized in that: include: Processed by the laser induced patterning device according to any one of claims 1 to 12; or comprising: The laser-induced patterning method according to any one of claims 13 to 18 is used for processing.

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