Doping device and method of tunneling oxide passivation contact solar cell

Abstract

The invention discloses a doping device and method for a tunneling oxide layer passivation contact solar cell, and relates to the technical field of doping. A conveying belt is used for conveying a to-be-doped product from a first position to a second position; the boron source chamber is located at a first position of the conveyor belt, and the conveyor belt penetrates through the boron source chamber; the boron source output unit is used for inputting a boron source into the boron source chamber; the first laser doping unit is used for performing first laser light doping on a to-be-doped product in the boron source chamber so as to form a first boron doping layer on the to-be-doped product; and the second laser doping unit is located at a second position of the conveyor belt, and the second laser doping unit is used for carrying out second laser light doping on the first boron doping layer on the to-be-doped product so as to form a second boron doping layer in a partial region on the first boron doping layer. Through the above design, the doping efficiency of the passivation contact solar cell of the tunneling oxide layer is improved.

Description

Technical Field

[0001] The present application relates to the field of doping technology, and in particular to a doping device and method for a tunnel oxide layer passivation contact solar cell. Background Art

[0002] In the current production process of tunnel oxide passivation contact solar cells, optimizing the boron doping step is crucial to improving cell performance and production efficiency. Traditional boron doping processes typically use a heating furnace, but this doping method is inefficient. Summary of the Invention

[0003] The purpose of the present application is to provide a doping device and method for a tunnel oxide layer passivation contact solar cell, thereby improving the doping efficiency of the tunnel oxide layer passivation contact solar cell.

[0004] The present application discloses a doping device for a tunneling oxide layer passivation contact solar cell, wherein the doping device for the tunneling oxide layer passivation contact solar cell is used to dope a product to be doped, and the doping device for the tunneling oxide layer passivation contact solar cell comprises:

[0005] A conveyor belt, comprising a first position and a second position, and configured to transport the product to be doped from the first position to the second position;

[0006] a boron source chamber, wherein the boron source chamber is located at a first position of the conveyor belt, and the conveyor belt passes through the boron source chamber;

[0007] a boron source output unit, the boron source output unit being connected to the boron source chamber and configured to input a boron source into the boron source chamber;

[0008] a first laser doping unit, the first laser doping unit being located on the boron source chamber and being used for performing a first laser light doping on the product to be doped in the boron source chamber to form a first boron doping layer on the product to be doped;

[0009] A second laser doping unit is located at a second position of the conveyor belt, and is used to perform a second laser light doping on the first boron doping layer on the doped product to form a second boron doping layer in a partial area on the first boron doping layer.

[0010] Optionally, the first laser doping unit includes at least one group of line spot laser emitting components, and the line spot laser emitting components include a first laser emitter, a first diffraction optical element and a light reflector, the diffraction optical element is located between the first laser emitter and the light reflector, the laser emitter is used to emit laser; the first diffraction optical element is used to shape the laser emitted by the first laser emitter to form a long rectangular spot; the light reflector is used to reflect the laser after being shaped by the diffraction optical element to the product to be doped.

[0011] Optionally, the second laser doping unit includes a second laser emitter, a second diffractive optical element, a collimating lens and a scanning galvanometer, wherein the second diffractive optical element is located between the second laser emitter and the collimating lens, and the collimating lens is located between the second diffractive optical element and the scanning galvanometer;

[0012] The second laser emitter is used to emit laser; the second diffraction optical element is used to split the laser emitted by the second laser emitter to form multiple laser beams; the collimating lens is used to collimate the multiple laser beams formed by the second diffraction optical element; the scanning galvanometer is used to control the deflection path of the multiple laser beams after collimation by the collimating lens to form a dot matrix laser, and irradiate it onto the first boron-doped layer of the product to be doped.

[0013] Optionally, the doping device of the tunnel oxide passivation contact solar cell further includes a driving motor and a speed adjustment unit, the driving motor is connected to the conveyor belt, the speed adjustment unit is connected to the driving motor, and the speed adjustment unit is used to control the movement speed of the conveyor belt.

[0014] Optionally, the first laser doping unit includes two groups of line spot laser emitting components, which are defined as a first group of line spot laser emitting components and a second group of line spot laser emitting components respectively; the long rectangular light spot generated by the first group of line spot laser emitting components is defined as a first doping light spot, and the long rectangular light spot generated by the second group of line spot laser emitting components is defined as a second doping light spot;

[0015] A direction from the first position toward the second position is defined as a first direction, the product to be doped includes a first doping region and a second doping region, and the second doping region is located on a side of the first doping region facing the first direction;

[0016] The first doping light spot is used to at least illuminate the first doping region, and the second doping light spot is used to illuminate the second doping region.

[0017] Optionally, the first laser doping unit includes three groups of line spot laser emitting components, which are respectively defined as a first group of line spot laser emitting components, a second group of line spot laser emitting components, and a third group of line spot laser emitting components; the long rectangular light spot generated by the first group of line spot laser emitting components is defined as a first doping spot, the long rectangular light spot generated by the second group of line spot laser emitting components is defined as a second doping spot, and the long rectangular light spot generated by the third group of line spot laser emitting components is defined as a third doping spot;

[0018] A direction along the first position toward the second position is defined as a first direction, the product to be doped includes a first doping region, a second doping region, and a third doping region, the second doping region is located on a side of the first doping region facing the first direction, and the third doping region is located on a side of the second doping region facing the first direction;

[0019] The first doping light spot is used to at least illuminate the first doping region, the second doping light spot is used to at least illuminate the second doping region, and the third doping light spot is used to illuminate the third doping region.

[0020] The present application also discloses a doping method for a tunneling oxide layer passivation contact solar cell. The doping method for a tunneling oxide layer passivation contact solar cell is used for the doping device for the tunneling oxide layer passivation contact solar cell described above. The doping method for a tunneling oxide layer passivation contact solar cell comprises the following steps:

[0021] S1: providing a product to be doped and placing it on the first position of the conveyor belt;

[0022] S2: Control the boron source output unit to input the boron source into the boron source chamber;

[0023] S3: When the boron source concentration in the boron source chamber reaches a preset concentration, the conveyor belt is controlled to drive the product to be doped to start moving;

[0024] S4: After the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped, so as to form a first boron doping layer on the product to be doped;

[0025] S5: After the product to be doped moves to the second preset position, the second laser doping unit is controlled to perform a second laser doping on a portion of the first boron doping layer on the product to be doped, so as to form a second boron doping layer on the first boron doping layer.

[0026] Optionally, in the step of S4: after the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped to form a first boron doping layer on the product to be doped:

[0027] The first laser doping unit forms a first boron doping layer with a thickness of 60nm-100nm on the product to be doped. The concentration of the first boron doping layer is 6×10 15 cm -3 .

[0028] Optionally, the first laser doping unit includes at least one group of line spot laser emitting components, and the line spot laser emitting components include a first laser emitter, a first diffraction optical element and a light reflecting mirror;

[0029] The boron source concentration of the boron source chamber is 200 sccm-350 sccm, the output power of the first laser emitter is 600 W, and the movement speed of the conveyor belt is 0.5 mm / s-5 mm / s.

[0030] Optionally, the first laser doping unit includes two groups of line spot laser emitting components, which are defined as a first group of line spot laser emitting components and a second group of line spot laser emitting components respectively; the long rectangular light spot generated by the first group of line spot laser emitting components is defined as a first doping spot, and the long rectangular light spot generated by the second group of line spot laser emitting components is defined as a second doping spot; the direction from the first position toward the second position is defined as a first direction, and the product to be doped includes a first doping region and a second doping region, and the second doping region is located on the side of the first doping region facing the first direction;

[0031] The step S4: after the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped to form a first boron doping layer on the product to be doped includes:

[0032] S41: After the product to be doped moves to the first preset position, the second group of line spot laser emitting assemblies are controlled to emit a second doping light spot to irradiate a position of the second doping region away from the first doping region, and the first group of line spot laser emitting assemblies are controlled to emit a first doping light spot to irradiate a position of the first doping region close to the second doping region;

[0033] S42: after the conveyor belt controls the movement of the product to be doped so that the first doping light spot emitted by the first group of line light spot laser emitting components scans the first doping area, the first group of line light spot laser emitting components is turned off;

[0034] S43: After the conveyor belt controls the movement of the product to be doped so that the second doping light spot emitted by the second group of line spot laser emitting assemblies scans the second doping region, a portion of the second doping light spot emitted by the second group of line spot laser emitting assemblies is controlled to illuminate a position of the first doping region close to the second doping region;

[0035] The energy of the second doping light spot gradually decreases along the opposite direction of the first direction, and the energy of the first doping light spot gradually decreases along the first direction.

[0036] Compared with the existing scheme of doping device for tunneling oxide passivation contact solar cells, the present application sets a boron source chamber on a conveyor belt, and then uses the first laser doping unit to perform a first laser light doping on the product to be doped in the boron source chamber to form a first boron doping layer on the product to be doped, and then uses the second laser doping unit to perform a second laser light doping on the first boron doping layer on the product to be doped to form a second boron doping layer in a partial area on the first boron doping layer; this realizes the streamlining of the doping process of tunneling oxide passivation contact solar cells and improves the doping efficiency of tunneling oxide passivation contact solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without inventive work. In the drawings:

[0038] Figure 1 1 is a schematic diagram of a doping device for a tunnel oxide passivation contact solar cell according to an embodiment of the present application;

[0039] Figure 2 is a schematic diagram of a product to be doped according to an embodiment of the present application;

[0040] Figure 3 This is a schematic diagram of a tunnel oxide layer passivation contact solar cell after doping of a product to be doped according to one embodiment of the present application;

[0041] Figure 4 is a schematic diagram of a plane of a product to be doped according to an embodiment of the present application;

[0042] Figure 5 This is a schematic diagram of a two-group linear spot laser emission assembly according to an embodiment of the present application;

[0043] Figure 6 is a schematic diagram of a driving motor and a speed adjustment unit according to an embodiment of the present application;

[0044] Figure 7 This is a schematic diagram of a driving motor and a speed adjustment unit according to an embodiment of the present application.

[0045] Among them, 10, tunneling oxide passivation contact doping device for solar cell; 20, product to be doped; 21, first doping region; 22, second doping region; 23, third doping region; 30, back electrode; 31, first silicon nitride layer; 32, phosphorus-doped layer; 33, tunneling silicon dioxide layer; 34, intrinsic layer; 35, first boron-doped layer; 36, second boron-doped layer; 37, aluminum oxide passivation layer; 38, second silicon nitride layer; 39, front electrode; 41, first direction; 100, conveyor belt; 110, first position; 120, second position; 130, drive motor; 140, speed adjustment unit; 200, boron source chamber; 210, conveyor belt entrance and exit; 220, boron source entrance; 230, gas outlet; 240, laser entrance; 250, concentration detection unit; 260, infrared sensing unit; 300, boron source output unit; 400, first laser doping unit; 410, line spot laser emission assembly; 411, first laser emitter; 412, first diffraction optical element; 413, light reflector; 421, first doping spot; 422, second doping spot; 423, third doping spot; 500, second laser doping unit; 510, second laser emitter; 520, second diffraction optical element; 530, collimating lens; 540, scanning galvanometer. DETAILED DESCRIPTION

[0046] It should be understood that the terms used herein, the specific structures and functional details disclosed are only for describing specific embodiments and are representative. However, the present application can be implemented in many alternative forms and should not be construed as being limited to the embodiments described herein.

[0047] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate relative importance or implicitly specify the quantity of the technical features indicated. Therefore, unless otherwise specified, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features; "plurality" means two or more. The term "comprising" and any variations thereof are intended to be non-exclusive inclusion, and one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0048] In addition, terms indicating orientation or positional relationships such as “center,” “lateral,” “up,” “down,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inside,” and “outside” are described based on the orientation or relative positional relationships shown in the accompanying drawings. They are merely simplified descriptions for the convenience of describing the present application, and do not indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present application.

[0049] Furthermore, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly, and may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0050] The present application is described in detail below with reference to the accompanying drawings and optional embodiments.

[0051] Figure 1 Schematic diagram of a doping device for a tunnel oxide passivation contact solar cell according to an embodiment of the present application. Figure 2 This is a schematic diagram of a product to be doped according to an embodiment of the present application. Figure 3 This is a schematic diagram of a tunnel oxide layer passivation contact solar cell after the doping of the doped product is completed in one embodiment of the present application, combined with Figure 1-Figure 3 As shown, the present application discloses a doping device 10 for a tunnel oxide layer passivation contact solar cell.

[0052] The doping device 10 for a tunneling oxide layer passivation contact solar cell is used to dope a product to be doped 20. The doping device 10 for a tunneling oxide layer passivation contact solar cell comprises:

[0053] The conveyor belt 100 includes a first position 110 and a second position 120 . The conveyor belt 100 is used to transport the product 20 to be doped from the first position 110 to the second position 120 .

[0054] The boron source chamber 200 is located on the first position 110 of the conveyor belt 100 , and the conveyor belt 100 passes through the boron source chamber 200 .

[0055] The boron source output unit 300 is connected to the boron source chamber 200 , and is used to input the boron source into the boron source chamber 200 .

[0056] The first laser doping unit 400 is located on the boron source chamber 200 and is used to perform a first laser light doping on the product to be doped 20 in the boron source chamber 200 to form a first boron doping layer 35 on the product to be doped 20.

[0057] The second laser doping unit 500 is located at the second position 120 of the conveyor belt 100. The second laser doping unit 500 is used to perform a second laser light doping on the first boron doping layer 35 on the doped product 20 to form a second boron doping layer 36 in a partial area on the first boron doping layer 35.

[0058] A conveyor belt entrance and exit 210 is provided at the bottom of the boron source chamber 200, a boron source inlet 220 and a gas outlet 230 are provided on the side wall of the boron source chamber 200, a laser inlet 240 is provided at the top of the boron source chamber 200, a boron source output unit 300 is connected to the boron source inlet 220, the conveyor belt 100 passes through the conveyor belt entrance and exit 210, and the laser emitted by the first laser doping unit 400 enters the boron source chamber 200 from the laser inlet 240.

[0059] See also Figure 2 and Figure 3 The product to be doped 20 includes a back electrode 30, a first silicon nitride layer 31, a phosphorus-doped layer 32, a tunneling silicon dioxide layer 33 and an intrinsic layer 34, and the back electrode 30, the silicon nitride layer 31, the phosphorus-doped layer 32, the tunneling silicon dioxide layer 33 and the intrinsic layer 34 are arranged in sequence; the tunneling oxide layer passivation contact solar cell also includes a first boron-doped layer 35, a second boron-doped layer 36, an aluminum oxide passivation layer 37, a second silicon nitride layer 38 and a front electrode 39, and the second boron-doped layer 36 is located at the junction of the front electrode 39 and the first boron-doped layer 35.

[0060] It can be understood that the first boron-doped layer 35 is a lightly doped layer, and the second boron-doped layer 36 is a heavily doped layer.

[0061] In the current production process of tunnel oxide passivation contact solar cells, the boron doping process is usually divided into the first high-temperature doping and the second laser doping, wherein the first high-temperature doping needs to be carried out in a heating furnace.

[0062] Compared with the existing scheme of doping device for tunneling oxide passivation contact solar cells, the present application sets a boron source chamber 200 on the conveyor belt 100, and then uses the first laser doping unit 400 to perform a first laser light doping on the product to be doped 20 in the boron source chamber 200 to form a first boron doping layer 35 on the product to be doped 20, and then uses the second laser doping unit 500 to perform a second laser light doping on the first boron doping layer 35 on the product to be doped 20 to form a second boron doping layer 36 in a partial area on the first boron doping layer 35; the doping process of tunneling oxide passivation contact solar cells is streamlined, and the doping efficiency of tunneling oxide passivation contact solar cells is improved.

[0063] Moreover, compared with placing the product to be doped 20 into a high-temperature furnace for high-temperature doping, the doping method using the first laser doping unit 400 consumes less energy; it can also avoid deviations in local doping concentration due to uneven thermal field distribution, and the doping is more uniform.

[0064] Furthermore, when adjusting the doping concentration of the first boron-doped layer 35 and the second boron-doped layer 36, the present application can precisely adjust the doping concentration by controlling the laser power of the first laser doping unit 400 and the second laser doping unit 500 or the speed of the conveyor belt 100. Compared with the indirect control method of a high-temperature furnace relying on temperature gradients, the process parameters are more responsive and the precision control is more accurate, thus meeting the production needs of products with multiple specifications.

[0065] See also Figure 1 The first laser doping unit 400 includes at least one group of line spot laser emitting components 410, and the line spot laser emitting components 410 include a first laser emitter 411, a first diffraction optical element 412 and a light reflector 413. The diffraction optical element is located between the first laser emitter 411 and the light reflector 413. The laser emitter is used to emit laser; the first diffraction optical element 412 is used to shape the laser emitted by the first laser emitter 411 to form a long rectangular spot; the light reflector 413 is used to reflect the laser shaped by the diffraction optical element onto the product to be doped 20.

[0066] The laser beam emitted by the first laser emitter 411 has a wavelength of 500nm-1100nm, a beam quality M2 factor of less than 1.1, an output power of 100W-1000W, a pulse width of 2ns-350ns, and an adjustable frequency of 1kHz-100kHz. The first laser emitter 411 has beam expansion and collimation functions, and the original spot shape emitted by the first laser emitter 411 is circular with a diameter of 5mm-8mm. The first diffractive optical element 412 adjusts the original spot emitted by the first laser emitter 411 to a 0.2mm*12mm long rectangular spot, the same width as the product to be doped 20. When the width of the product to be doped 20 changes, the length of the long rectangular spot can also be adaptively adjusted.

[0067] The second laser doping unit 500 includes a second laser emitter 510, a second diffractive optical element 520, a collimating lens 530 and a scanning galvanometer 540. The second diffractive optical element 520 is located between the second laser emitter 510 and the collimating lens 530, and the collimating lens 530 is located between the second diffractive optical element 520 and the scanning galvanometer 540.

[0068] The second laser emitter 510 is used to emit laser; the second diffraction optical element 520 is used to split the laser emitted by the second laser emitter 510 to form multiple laser beams; the collimating lens 530 is used to collimate the multiple laser beams formed by the second diffraction optical element 520; the scanning galvanometer 540 is used to control the deflection path of the multiple laser beams after collimation by the collimating lens 530 to form a dot matrix laser, and irradiate it onto the first boron-doped layer 35 of the product to be doped 20.

[0069] The laser beam emitted by the second laser emitter 510 has a wavelength of 355nm-1100nm, a beam quality M2 factor less than 1.1, an output power of 1W-300W, a pulse width of 100fs-100ns, and a frequency of 1kHz-100kHz. The second laser emitter 510 also has beam expansion and collimation functions. The original light spot emitted by the second laser emitter 510 is circular in shape, with a diameter of 1mm-10mm. The second diffractive optical element 520 splits the original light spot emitted by the second laser emitter 510 into multiple beams, the specific number of which can be adjusted based on the number of front electrodes 39 on the product 20 to be doped.

[0070] Figure 4 This is a schematic diagram of a plane of a product to be doped according to an embodiment of the present application, combined with Figure 4 As shown, in order to further improve the doping speed, the first laser doping unit 400 of the present application may include three groups of line spot laser emitting components 410, which are used to dope the three areas of the product 20 to be doped respectively. The first laser doping unit 400 includes three groups of line spot laser emitting components 410, which are defined as the first group of line spot laser emitting components 410, the second group of line spot laser emitting components 410 and the third group of line spot laser emitting components 410 respectively; the long rectangular spot generated by the first group of line spot laser emitting components 410 is defined as the first doping spot 421, the long rectangular spot generated by the second group of line spot laser emitting components 410 is defined as the second doping spot 422, and the long rectangular spot generated by the third group of line spot laser emitting components 410 is defined as the third doping spot 423.

[0071] The direction along the first position 110 toward the second position 120 is defined as a first direction 41. The product to be doped 20 includes a first doping region 21, a second doping region 22 and a third doping region 23. The second doping region 22 is located on the side of the first doping region 21 facing the first direction 41, and the third doping region 23 is located on the side of the second doping region 22 facing the first direction 41.

[0072] The first doping light spot 421 is used to at least illuminate the first doping region 21 , the second doping light spot 422 is used to at least illuminate the second doping region 22 , and the third doping light spot 423 is used to illuminate the third doping region 23 .

[0073] It can be understood that the product to be doped 20 is divided into a first doping region 21, a second doping region 22 and a third doping region 23 from left to right, the first group of line spot laser emitting components 410 scans the first doping region 21 from right to left, the second group of line spot laser emitting components 410 scans the second doping region 22 from right to left, and the third group of line spot laser emitting components 410 scans the third doping region 23 from right to left, thereby completing the scanning of the entire product to be doped 20 and improving the doping speed.

[0074] Moreover, when the product to be doped 20 moves onto the second laser doping unit 500 , the temperature of the entire surface of the first boron doping layer 35 is more uniform, thereby ensuring that the doping concentration and thickness of the second boron doping layer 36 are more balanced.

[0075] Of course, it is also possible that, when the product to be doped 20 needs to be doped with a high concentration, the entire surface of the product to be doped 20 is scanned in sequence by the first group of line spot laser emitting components 410, the second group of line spot laser emitting components 410 and the third group of line spot laser emitting components 410, and the concentration of the first boron doping layer 35 can be adjusted without changing the boron source concentration in the boron source chamber 200 and without changing the movement speed of the conveyor belt 100.

[0076] Figure 5 2 is a schematic diagram of two groups of line spot laser emitting assemblies according to an embodiment of the present application. Of course, the first laser doping unit 400 may also include two groups of line spot laser emitting assemblies 410, which are respectively defined as a first group of line spot laser emitting assemblies 410 and a second group of line spot laser emitting assemblies 410; the long rectangular light spot generated by the first group of line spot laser emitting assemblies 410 is defined as a first doping light spot 421, and the long rectangular light spot generated by the second group of line spot laser emitting assemblies 410 is defined as a second doping light spot 422;

[0077] The direction from the first position 110 toward the second position 120 is defined as a first direction 41 . The product to be doped 20 includes a first doping region 21 and a second doping region 22 . The second doping region 22 is located on a side of the first doping region 21 facing the first direction 41 .

[0078] The first doping light spot 421 is used to at least illuminate the first doping region 21 , and the second doping light spot 422 is used to illuminate the second doping region 22 .

[0079] Compared with the solution in which the first laser doping unit 400 includes three groups of linear spot laser emitting components 410, the first laser doping unit 400 includes only two groups of linear spot laser emitting components 410, which is lower in cost, has fewer partitions for the doped product 20, fewer intersections, and more uniform doping.

[0080] Figure 6 This is a schematic diagram of a driving motor and a speed regulating unit according to an embodiment of the present application. The doping device 10 for the tunnel oxide passivation contact solar cell further includes a driving motor 130 and a speed regulating unit 140. The driving motor 130 is connected to the conveyor belt 100, and the speed regulating unit 140 is connected to the driving motor 130. The speed regulating unit 140 is used to control the movement speed of the conveyor belt 100.

[0081] The speed regulating unit 140 can control the movement speed of the conveyor belt 100, thereby controlling the movement speed of the product to be doped 20, thereby controlling the irradiation time of the first laser doping unit 400 to control the doping concentration of the first boron doping layer 35, and controlling the irradiation time of the second laser doping unit 500 to control the doping concentration of the second boron doping layer 36.

[0082] Figure 7 This is a schematic diagram of a driving motor and a speed adjustment unit according to an embodiment of the present application, Figure 1-Figure 7 The present application also discloses a doping method for a tunneling oxide passivation contact solar cell. The doping method for a tunneling oxide passivation contact solar cell is used in the doping device 10 for the tunneling oxide passivation contact solar cell described above. The steps of the doping method for a tunneling oxide passivation contact solar cell include:

[0083] S1: providing a product to be doped and placing it on the first position of the conveyor belt;

[0084] It is understood that the product to be doped 20 is placed on the first position 110 of the conveyor belt 100 with the intrinsic layer 34 facing upwards.

[0085] S2: Control the boron source output unit to input the boron source into the boron source chamber;

[0086] Illustratively, the boron source is boron trichloride.

[0087] S3: When the boron source concentration in the boron source chamber reaches a preset concentration, the conveyor belt is controlled to drive the product to be doped to start moving;

[0088] For example, to determine whether the boron source concentration in the boron source chamber 200 reaches a preset concentration, a concentration detection unit 250 can be set to detect the boron source concentration in the boron source chamber 200, or the boron source concentration in the boron source chamber 200 can be determined by determining the time of introduction.

[0089] S4: After the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped, so as to form a first boron doping layer on the product to be doped;

[0090] The first preset position is the initial position where the first laser doping unit 400 can irradiate the region to be doped of the product to be doped 20. For example, to determine whether the product to be doped 20 has moved to the first preset position, an infrared sensing unit 260 can be provided to detect whether the product to be doped 20 has moved to the first preset position.

[0091] S5: After the product to be doped moves to the second preset position, the second laser doping unit is controlled to perform a second laser doping on a portion of the first boron doping layer on the product to be doped, so as to form a second boron doping layer on the first boron doping layer.

[0092] The second preset position is an initial position where the second laser doping unit 500 can irradiate the region requiring doping of the first boron doping layer 35 of the product to be doped 20 .

[0093] Compared with the existing doping method of tunneling oxide passivation contact solar cells, the present application sets a boron source chamber 200 on the conveyor belt 100, and then uses the first laser doping unit 400 to perform a first laser light doping on the product to be doped 20 in the boron source chamber 200 to form a first boron doping layer 35 on the product to be doped 20, and then uses the second laser doping unit 500 to perform a second laser light doping on the first boron doping layer 35 on the product to be doped 20 to form a second boron doping layer 36 in a partial area on the first boron doping layer 35; the doping process of the tunneling oxide passivation contact solar cell is streamlined, and the doping efficiency of the tunneling oxide passivation contact solar cell is improved.

[0094] Moreover, compared with placing the product to be doped 20 into a high-temperature furnace for high-temperature doping, the doping method using the first laser doping unit 400 consumes less energy; it can also avoid deviations in local doping concentration due to uneven thermal field distribution, and the doping is more uniform.

[0095] Furthermore, when adjusting the doping concentration of the first boron-doped layer 35 and the second boron-doped layer 36, the present application can precisely adjust the concentration by controlling the laser power or the speed of the conveyor belt 100. Compared with the indirect control method of a high-temperature furnace that relies on temperature gradients, the process parameters are more responsive and the precision control is more accurate, thus meeting the production needs of products with multiple specifications.

[0096] For example, since the temperature of the first boron-doped layer 35 is between 900°C and 1100°C after the first laser doping unit 400 performs doping to form the first boron-doped layer 35, and the natural cooling time is 20-30°C / min, in order to avoid the temperature of the first boron-doped layer 35 from dropping too low, the product to be doped 20 is controlled to move from the first preset position to the second preset position within 1min-2min.

[0097] In the step S4: after the product to be doped 20 moves to the first preset position, controlling the first laser doping unit 400 to perform a first laser doping on the product to be doped 20 to form a first boron doping layer 35 on the product to be doped 20:

[0098] The first laser doping unit 400 forms a first boron doping layer 35 on the product to be doped 20 with a thickness of 60 nm to 100 nm. The concentration of the first boron doping layer 35 is 6×10 15 cm -3 .

[0099] The first laser doping unit 400 forms a layer with a thickness of 60 nm to 100 nm and a concentration of 6×10 15 cm -3 The first boron doping layer 35 is formed, so that the residual boron source is sufficient to ensure the smooth doping of the second laser doping unit 500.

[0100] The first laser doping unit 400 includes at least one group of line spot laser emitting components 410, and the line spot laser emitting components 410 include a first laser emitter 411, a first diffraction optical element 412 and a light reflecting mirror 413; the boron source concentration of the boron source chamber 200 is 200sccm-350sccm, the output power of the first laser emitter 411 is 600W, and the movement speed of the conveyor belt 100 is 0.5mm / s-5mm / s.

[0101] The concentration and thickness of the first boron-doped layer 35 can be adjusted by controlling the moving speed of the conveyor belt 100 .

[0102] Exemplarily, the first laser doping unit 400 includes two groups of line spot laser emitting components 410, which are respectively defined as the first group of line spot laser emitting components 410 and the second group of line spot laser emitting components 410; the long rectangular spot generated by the first group of line spot laser emitting components 410 is defined as the first doping spot 421, and the long rectangular spot generated by the second group of line spot laser emitting components 410 is defined as the second doping spot 422; the direction along the first position 110 toward the second position 120 is defined as the first direction 41, and the product to be doped 20 includes a first doping region 21 and a second doping region 22, and the second doping region 22 is located on the side of the first doping region 21 facing the first direction 41.

[0103] The step S4: after the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped to form a first boron doping layer on the product to be doped includes:

[0104] S41: After the product to be doped moves to the first preset position, the second group of line spot laser emitting assemblies are controlled to emit a second doping light spot to irradiate a position of the second doping region away from the first doping region, and the first group of line spot laser emitting assemblies are controlled to emit a first doping light spot to irradiate a position of the first doping region close to the second doping region;

[0105] S42: after the conveyor belt controls the movement of the product to be doped so that the first doping light spot emitted by the first group of line light spot laser emitting components scans the first doping area, the first group of line light spot laser emitting components is turned off;

[0106] S43: After the conveyor belt controls the movement of the product to be doped so that the second doping light spot emitted by the second group of line spot laser emitting assemblies scans the second doping region, a portion of the second doping light spot emitted by the second group of line spot laser emitting assemblies is controlled to illuminate a position of the first doping region close to the second doping region;

[0107] In simple terms, the scanning area of ​​the second doping light spot 422 is controlled to partially overlap with the scanning area of ​​the first doping light spot 421, and the width of the overlapping area is smaller than the width of the second doping light spot 422. The energy of the second doping light spot 422 gradually decreases in the opposite direction of the first direction 41, and the energy of the first doping light spot 421 gradually decreases in the first direction 41.

[0108] Since the first doping region 21 is scanned by the first doping spot 421 and the second doping region 22 is scanned by the second doping spot 422 , in order to avoid the phenomenon of high doping concentration or no doping at the position between the first doping region 21 and the second doping region 22 .

[0109] In the present application, the energy of the second doping spot 422 is gradually reduced along the opposite direction of the first direction 41, and the energy of the first doping spot 421 is gradually reduced along the first direction 41, and then the scanning area of ​​the second doping spot 422 is controlled to overlap with the scanning area of ​​the first doping spot 421, and the energy of the second doping spot 422 is controlled to gradually decrease along the opposite direction of the first direction 41, and the energy of the first doping spot 421 is gradually reduced along the first direction 41. In this way, the doping concentration will not be too high at the position where the scanning area of ​​the first doping spot 421 and the scanning area of ​​the second doping spot 422 overlap, thereby improving the doping efficiency while avoiding uneven doping.

[0110] It should be noted that the limitations on the steps involved in this solution do not limit the order of the steps without affecting the implementation of the specific solution. The steps written in front can be executed first, later, or even simultaneously. As long as this solution can be implemented, it should be deemed to fall within the scope of protection of this application.

[0111] It should be noted that the inventive concept of this application can form a large number of embodiments, but the length of the application document is limited and it is impossible to list them one by one. Therefore, under the premise of no conflict, the various embodiments or technical features described above can be arbitrarily combined to form new embodiments. After the various embodiments or technical features are combined, the original technical effects will be enhanced.

[0112] The above content is a further detailed description of the present application in conjunction with specific optional implementation methods, and the specific implementation of the present application cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, they can make several simple deductions or substitutions without departing from the concept of the present application, which should be considered to fall within the scope of protection of the present application.

Claims

1. A doping device for a tunnel oxide passivation contact solar cell, characterized in that: The doping device of the tunnel oxide layer passivation contact solar cell is used to dope a product to be doped, and the doping device of the tunnel oxide layer passivation contact solar cell comprises: A conveyor belt, comprising a first position and a second position, and configured to transport the product to be doped from the first position to the second position; a boron source chamber, wherein the boron source chamber is located at a first position of the conveyor belt, and the conveyor belt passes through the boron source chamber; a boron source output unit, the boron source output unit being connected to the boron source chamber and configured to input a boron source into the boron source chamber; a first laser doping unit, the first laser doping unit being located on the boron source chamber and being used for performing a first laser light doping on the product to be doped in the boron source chamber to form a first boron doping layer on the product to be doped; A second laser doping unit is located at a second position of the conveyor belt, and is used to perform a second laser light doping on the first boron doping layer on the doped product to form a second boron doping layer in a partial area on the first boron doping layer.

2. The doping device for a tunnel oxide passivation contact solar cell according to claim 1, characterized in that: The first laser doping unit includes at least one group of line spot laser emitting components, which include a first laser emitter, a first diffraction optical element and a light reflector. The diffraction optical element is located between the first laser emitter and the light reflector. The laser emitter is used to emit laser; the first diffraction optical element is used to shape the laser emitted by the first laser emitter to form a long rectangular light spot; the light reflector is used to reflect the laser shaped by the diffraction optical element onto the product to be doped.

3. The doping device for a tunnel oxide passivation contact solar cell according to claim 2, characterized in that: The second laser doping unit includes a second laser emitter, a second diffractive optical element, a collimating lens and a scanning galvanometer, wherein the second diffractive optical element is located between the second laser emitter and the collimating lens, and the collimating lens is located between the second diffractive optical element and the scanning galvanometer; The second laser emitter is used to emit laser; the second diffraction optical element is used to split the laser emitted by the second laser emitter to form multiple laser beams; the collimating lens is used to collimate the multiple laser beams formed by the second diffraction optical element; the scanning galvanometer is used to control the deflection path of the multiple laser beams after collimation by the collimating lens to form a dot matrix laser, and irradiate it onto the first boron-doped layer of the product to be doped.

4. The doping device for a tunnel oxide passivation contact solar cell according to claim 1, characterized in that: The doping device for the tunnel oxide passivation contact solar cell further includes a driving motor and a speed regulating unit. The driving motor is connected to the conveyor belt, and the speed regulating unit is connected to the driving motor. The speed regulating unit is used to control the movement speed of the conveyor belt.

5. The doping device for a tunnel oxide passivation contact solar cell according to claim 2, characterized in that: The first laser doping unit includes two groups of line spot laser emitting components, which are defined as a first group of line spot laser emitting components and a second group of line spot laser emitting components respectively; the long rectangular light spot generated by the first group of line spot laser emitting components is defined as a first doping light spot, and the long rectangular light spot generated by the second group of line spot laser emitting components is defined as a second doping light spot; A direction from the first position toward the second position is defined as a first direction, the product to be doped includes a first doping region and a second doping region, and the second doping region is located on a side of the first doping region facing the first direction; The first doping light spot is used to at least illuminate the first doping region, and the second doping light spot is used to illuminate the second doping region.

6. The doping device for a tunnel oxide passivation contact solar cell according to claim 2, characterized in that: The first laser doping unit includes three groups of line spot laser emitting components, which are defined as a first group of line spot laser emitting components, a second group of line spot laser emitting components, and a third group of line spot laser emitting components; the long rectangular light spot generated by the first group of line spot laser emitting components is defined as a first doping light spot, the long rectangular light spot generated by the second group of line spot laser emitting components is defined as a second doping light spot, and the long rectangular light spot generated by the third group of line spot laser emitting components is defined as a third doping light spot; A direction along the first position toward the second position is defined as a first direction, the product to be doped includes a first doping region, a second doping region, and a third doping region, the second doping region is located on a side of the first doping region facing the first direction, and the third doping region is located on a side of the second doping region facing the first direction; The first doping light spot is used to at least illuminate the first doping region, the second doping light spot is used to at least illuminate the second doping region, and the third doping light spot is used to illuminate the third doping region.

7. A doping method for a tunnel oxide passivation contact solar cell, characterized in that: The doping method for a tunneling oxide layer passivation contact solar cell is used for the doping device for a tunneling oxide layer passivation contact solar cell according to any one of claims 1 to 6, and the steps of the doping method for a tunneling oxide layer passivation contact solar cell include: S1: providing a product to be doped and placing it on the first position of the conveyor belt; S2: Control the boron source output unit to input the boron source into the boron source chamber; S3: When the boron source concentration in the boron source chamber reaches a preset concentration, the conveyor belt is controlled to drive the product to be doped to start moving; S4: After the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped, so as to form a first boron doping layer on the product to be doped; S5: After the product to be doped moves to the second preset position, the second laser doping unit is controlled to perform a second laser doping on a portion of the first boron doping layer on the product to be doped, so as to form a second boron doping layer on the first boron doping layer.

8. The doping method for a tunnel oxide passivation contact solar cell according to claim 7, characterized in that: In the step S4: after the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped to form a first boron doping layer on the product to be doped: The first laser doping unit forms a first boron doping layer with a thickness of 60nm-100nm on the product to be doped. The concentration of the first boron doping layer is 6×10 15 cm -3 .

9. The doping method for a tunnel oxide passivation contact solar cell according to claim 8, characterized in that: The first laser doping unit includes at least one group of line spot laser emitting components, and the line spot laser emitting components include a first laser emitter, a first diffraction optical element and a light reflecting mirror; The boron source concentration of the boron source chamber is 200 sccm-350 sccm, the output power of the first laser emitter is 600 W, and the movement speed of the conveyor belt is 0.5 mm / s-5 mm / s.

10. The doping method for a tunnel oxide passivation contact solar cell according to claim 7, characterized in that: The first laser doping unit includes two groups of line spot laser emitting components, which are defined as a first group of line spot laser emitting components and a second group of line spot laser emitting components respectively; the long rectangular light spot generated by the first group of line spot laser emitting components is defined as a first doping spot, and the long rectangular light spot generated by the second group of line spot laser emitting components is defined as a second doping spot; the direction from the first position toward the second position is defined as a first direction, and the product to be doped includes a first doping region and a second doping region, and the second doping region is located on the side of the first doping region facing the first direction; The step S4: after the product to be doped moves to the first preset position, controlling the first laser doping unit to perform a first laser doping on the product to be doped to form a first boron doping layer on the product to be doped includes: S41: After the product to be doped moves to the first preset position, the second group of line spot laser emitting assemblies are controlled to emit a second doping light spot to irradiate a position of the second doping region away from the first doping region, and the first group of line spot laser emitting assemblies are controlled to emit a first doping light spot to irradiate a position of the first doping region close to the second doping region; S42: after the conveyor belt controls the movement of the product to be doped so that the first doping light spot emitted by the first group of line light spot laser emitting components scans the first doping area, the first group of line light spot laser emitting components is turned off; S43: After the conveyor belt controls the movement of the product to be doped so that the second doping light spot emitted by the second group of line spot laser emitting assemblies scans the second doping region, a portion of the second doping light spot emitted by the second group of line spot laser emitting assemblies is controlled to illuminate a position of the first doping region close to the second doping region; The energy of the second doping light spot gradually decreases along the opposite direction of the first direction, and the energy of the first doping light spot gradually decreases along the first direction.

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