Patent Application
20240165651
The present disclosure relates to the photovoltaic field, and specifically to a chain-type roller coating apparatus and use thereof.
In the production process of solar cells, silicon wafers need to be subjected to dopant diffusion treatment. Dopant diffusion can be divided into two steps: source deposition and source drive-in. The source deposition is to deposit a dopant source on a surface of a silicon wafer. The source drive-in is to perform heat treatment on the silicon wafer with the dopant source deposited, so that dopant elements diffuse into the silicon wafer.
A liquid dopant source may be used in the source deposition. The liquid dopant source is uniformly roller-coated on the surface of the silicon wafer by using a liquid coating roller. To supply the liquid dopant source to the liquid coating roller, a liquid squeezing roller, a liquid taking roller, and a liquid reservoir need to be arranged for the liquid coating roller. The liquid reservoir stores the liquid dopant source. A lower portion of the liquid taking roller is immersed in the liquid reservoir, and an upper portion of the liquid taking roller is located above the liquid reservoir. The liquid coating roller is located on an outer side of the liquid reservoir. The liquid squeezing roller is located between the liquid taking roller and the liquid coating roller. Two sides of the liquid squeezing roller are respectively in contact with the liquid taking roller and the liquid coating roller. The liquid dopant source is taken out from the liquid reservoir by the liquid taking roller. The liquid dopant source on the liquid taking roller is transferred to the liquid squeezing roller, rolled evenly by the liquid squeezing roller, then transferred to the liquid coating roller, and coated onto the surface of the silicon wafer by the liquid coating roller.
The liquid coating roller is a sponge roller having a soft outer surface, so as not to damage the silicon wafer. In the roller coating process, to ensure that the liquid squeezing roller can stably transfer the liquid dopant source to the sponge roller, it is necessary to control the degree by which the liquid squeezing roller is pressed into the sponge roller, so that a part of the sponge roller in contact with the liquid squeezing roller is in a local squeezed state. After shutdown, if the sponge roller remains in the local squeezed state for a long time, the sponge roller undergoes serious deformation, affecting the roller coating effect. Therefore, it is necessary to design a chain-type roller coating apparatus that can adjust the position of the liquid coating roller.
The present disclosure provides a chain-type roller coating apparatus that can adjust the position of a liquid coating roller, including a roller bed configured to convey a silicon wafer and a liquid coating roller horizontally arranged and configured for roller-coating a dopant source onto the silicon wafer on the roller bed,
Preferably, the synchronizing wheel, the proximity switch, the first lifting driving device, and the ranging sensor are supported by a frame.
Preferably, the liquid coating roller is equipped with a feeding mechanism configured to supply the dopant source to the liquid coating roller; the feeding mechanism includes a liquid reservoir configured to store a liquid dopant source, and a liquid taking roller and a liquid squeezing roller which are configured to transfer the liquid dopant source in the liquid reservoir to the liquid coating roller, and the liquid reservoir, the liquid taking roller, and the liquid squeezing roller are supported by the frame; the liquid taking roller and the liquid squeezing roller are horizontally arranged and parallel to the plurality of conveying rollers; a lower portion of the liquid taking roller is immersed in the liquid reservoir, and an upper portion of the liquid taking roller is located above the liquid reservoir; the liquid coating roller is located on an outer side of the liquid reservoir; and the liquid squeezing roller is located between the liquid taking roller and the liquid coating roller, and two sides of a bottom portion of the liquid squeezing roller are respectively in contact with the liquid taking roller and the liquid coating roller.
Preferably, the frame is equipped with a second lifting driving device configured to drive the frame to ascend or descend vertically.
Preferably, the mounting hole is a rectangular hole, and the shaft protrusion portion is in a shape of a rectangular bar.
Preferably, the shaft protrusion portion is coaxial with the shaft main body.
Preferably, the rotation support device includes a bearing sleeved over the shaft main body and a connecting member connected to the bearing and the first lifting driving device.
Preferably, the first lifting driving device is a linear motor or a linear cylinder.
Preferably, the trigger element is arranged on an outer end surface of the synchronizing wheel.
Preferably, the proximity switch is located above the synchronizing wheel, and the trigger element extends to a periphery of the synchronizing wheel.
The present disclosure also provides a use of the chain-type roller coating apparatus, where the chain-type roller coating apparatus is applied to a chain-type diffusion process, a chain-type gettering process, or a laser-doped selective emitter (SE) process.
The advantages and beneficial effects of the present disclosure are as follows. In the chain-type roller coating apparatus of the present disclosure, a spacing between the liquid coating roller and the liquid squeezing roller can be adjusted, the degree by which the liquid squeezing roller is pressed into the liquid coating roller can be controlled, and the separation of the liquid coating roller from the liquid squeezing roller can also be realized, to avoid the serious deformation of the liquid coating roller due to the liquid coating roller still being in the local squeezed state after shutdown, thereby prolonging the service life of the liquid coating roller, and ensuring the roller coating effect.
The chain-type roller coating apparatus of the present disclosure is applicable to a chain-type diffusion process, a chain-type gettering process, or a laser-doped selective emitter process, and the chain-type roller coating apparatus is suitable for producing TOPCon (Tunnel Oxide Passivated Contact) cells or HJT (Heterojunction) cells, and realizes a fully automated production line, thereby improving the production efficiency.
The specific embodiments of the present disclosure will be described in further detail with reference to the accompanying drawings and examples. The following embodiments are merely used for more clearly describing the technical solutions of the present disclosure, and are not intended to limit the protection scope of the present disclosure.
The following technical solutions are employed in the present disclosure.
As shown in
The roller bed includes a plurality of conveying rollers arranged sequentially along a conveying direction of the roller bed and a transmission mechanism configured to drive the plurality of conveying rollers to rotate. The plurality of conveying rollers are horizontally arranged and parallel to each other.
The liquid coating roller 1 is parallel to the plurality of conveying rollers. The liquid coating roller 1 is equipped with a synchronizing wheel 2 configured to drive the liquid coating roller 1 to rotate. The synchronizing wheel 2 is located on an outer side of an axial end of the liquid coating roller 1. An axis of the synchronizing wheel 2 is parallel to an axis of the liquid coating roller 1, and the axis of the synchronizing wheel 2 and the axis of the liquid coating roller 1 are located in an identical vertical plane. The synchronizing wheel 2 is equipped with a driving mechanism configured to drive the synchronizing wheel 2 to rotate.
The synchronizing wheel 2 is further provided with a mounting hole 21. The mounting hole 21 is a straight elongated hole. The mounting hole 21 extends along a radial direction of the synchronizing wheel 2. The mounting hole 21 extends across the axis of the synchronizing wheel 2. A proximity switch 3 is further arranged on an outer side of the synchronizing wheel 2. The proximity switch 3 and the axis of the synchronizing wheel 2 are located in an identical vertical plane. The synchronizing wheel 2 is further provided with a trigger element 4 which is configured to be sensed by the proximity switch 3. The trigger element 4 is located outside the mounting hole 21, and the trigger element 4 and the mounting hole 21 are located on an identical straight line. The proximity switch 3 is located above the synchronizing wheel 2, the trigger element 4 is arranged on an outer end surface of the synchronizing wheel 2, and the trigger element 4 extends to a periphery of the synchronizing wheel 2. The trigger element 4 is configured to rotate with the synchronizing wheel 2, and when the trigger element 4 is rotated to a position in which the trigger element is sensed by the proximity switch 3, the trigger element 4 and the axis of the synchronizing wheel 2 are located in an identical vertical plane.
The liquid coating roller 1 is assembled with the synchronizing wheel 2 by a connecting shaft 5. The connecting shaft 5 includes a shaft main body 51 which is connected to the liquid coating roller 1 and coaxial with the liquid coating roller 1, and a shaft protrusion portion 52 which extends from an end of the shaft main body 51 away from the liquid coating roller 1 and is inserted into the mounting hole 21. The shaft protrusion portion 52 is coaxial with the shaft main body 51. The mounting hole 21 is a rectangular hole, and the shaft protrusion portion 52 is in a shape of a rectangular bar. The shaft protrusion portion 52 is slidably engaged with the mounting hole 21.
The shaft main body 51 of the connecting shaft 5 is equipped with a rotation support device 6 configured to support a rotation of the shaft main body 51. The rotation support device 6 is located between the liquid coating roller 1 and the synchronizing wheel 2. The rotation support device 6 is equipped with a first lifting driving device 7 configured to drive the rotation support device 6 to ascend or descend vertically. The first lifting driving device 7 is a linear motor or a linear cylinder. The rotation support device 6 includes a bearing sleeved over the shaft main body 51 and a connecting member connected to the bearing and the first lifting driving device 7.
A ranging sensor 8 is arranged exactly above the liquid coating roller 1.
The synchronizing wheel 2, the proximity switch 3, the first lifting driving device 7, and the ranging sensor 8 are supported by a frame.
The liquid coating roller 1 is equipped with a feeding mechanism configured to supply the dopant source to the liquid coating roller 1. The feeding mechanism includes a liquid reservoir configured to store a liquid dopant source, and a liquid taking roller 91 and a liquid squeezing roller 92 which are configured to transfer the liquid dopant source in the liquid reservoir to the liquid coating roller 1, and the liquid reservoir, the liquid taking roller 91, and the liquid squeezing roller 92 are supported by the frame. The liquid taking roller 91 and the liquid squeezing roller 92 are horizontally arranged and parallel to the plurality of conveying rollers. A lower portion of the liquid taking roller 91 is immersed in the liquid reservoir, and an upper portion of the liquid taking roller 91 is located above the liquid reservoir. The liquid coating roller 1 is located on an outer side of the liquid reservoir. The liquid squeezing roller 92 is located between the liquid taking roller 91 and the liquid coating roller 1, and two sides of a bottom portion of the liquid squeezing roller 92 are respectively in contact with the liquid taking roller 91 and the liquid coating roller 1. The liquid taking roller 91 and the liquid squeezing roller 92 are each independently a smooth-surface roller, a threaded roller, an anilox roller, or a patterned roller. Outer surfaces of the conveying rollers, the liquid taking roller 91, and the liquid squeezing roller 92 are all made of a corrosion-resistant and pollution-free non-metallic material.
The frame is equipped with a second lifting driving device configured to drive the frame to ascend or descend vertically.
The roller bed conveys the silicon wafer. The liquid dopant source is taken out from the liquid reservoir by the liquid taking roller 91. The liquid dopant source on the liquid taking roller 91 is transferred to the liquid squeezing roller 92, rolled evenly by the liquid squeezing roller 92, then transferred to the liquid coating roller 1, and coated onto the surface of the silicon wafer by the liquid coating roller 1. A height of the frame can be adjusted by the second lifting driving device to control the degree by which the silicon wafer is pressed into the liquid coating roller 1, thereby controlling the deposition amount of the liquid dopant source on the surface of the silicon wafer.
The liquid coating roller 1 may be a sponge roller having a soft outer surface, so as not to damage the silicon wafer. In the roller coating process, to ensure that the liquid squeezing roller 92 can stably transfer the dopant source to the sponge roller, it is necessary to control the degree by which the liquid squeezing roller 92 is pressed into the sponge roller, so that a part of the sponge roller in contact with the liquid squeezing roller 92 is in a local squeezed state. After shutdown, the liquid coating roller 1 needs to be separated from the liquid squeezing roller 92, to avoid serious deformation of the liquid coating roller 1 due to the liquid coating roller 1 still being in the local squeezed state after shutdown.
To control the degree by which the liquid squeezing roller 92 is pressed into the sponge roller or to separate the liquid coating roller 1 from the liquid squeezing roller 92, the chain-type roller coating apparatus of the present disclosure is required to be capable of adjusting the position of the liquid coating roller 1. To be specific, the chain-type roller coating apparatus of the present disclosure is required to be capable of adjusting the spacing between the liquid coating roller 1 and the liquid squeezing roller 92.
In the present disclosure, the liquid coating roller 1 is assembled with the synchronizing wheel 2 by the connecting shaft 5, the shaft protrusion portion 52 of the connecting shaft 5 is inserted into the mounting hole 21 of the synchronizing wheel 2, both the liquid coating roller 1 and the connecting shaft 5 are supported by the rotation support device 6, and the rotation support device 6 is supported by the first lifting driving device 7.
When the liquid coating roller 1 operates normally, the liquid coating roller 1 is approximately coaxial with the synchronizing wheel 2, and the synchronizing wheel 2 drives, through the connecting shaft 5, the liquid coating roller 1 to rotate.
To adjust the spacing between the liquid coating roller 1 and the liquid squeezing roller 92, the second lifting driving device drives the frame to ascend, so that the liquid coating roller 1 is completely separated from the roller bed. Then, the synchronizing wheel 2 is rotated to cause the trigger element 4 to rotate, so that the trigger element 4 is rotated to the position in which the trigger element 4 can be sensed by the proximity switch 3. Upon detecting the trigger element 4, the proximity switch 3 stops the rotation of the synchronizing wheel 2. In this case, the trigger element 4 and the axis of the synchronizing wheel 2 are located in the identical vertical plane, the trigger element 4 and the mounting hole 21 are located on the identical straight line, and the mounting hole 21 extends along the radial direction of the synchronizing wheel 2 and extends across the axis of the synchronizing wheel 2. Therefore, when the trigger element 4 is rotated to the position in which the trigger element 4 can be sensed by the proximity switch 3, the mounting hole 21 is in a vertical state, i.e., the mounting hole 21 is in a state allowing the shaft protrusion portion 52 to move vertically in the mounting hole 21. After the mounting hole 21 enters the vertical state, the vertical positions of the rotation support device 6, the connecting shaft 5, and the liquid coating roller 1 may be adjusted by the first lifting driving device 7, so that the liquid coating roller 1 can move relative to the liquid squeezing roller 92 in the vertical direction. A displacement of the liquid coating roller 1 in the vertical direction may be detected by the ranging sensor 8, so as to control the spacing between the liquid coating roller 1 and the liquid squeezing roller 92, and further adjust the degree by which the liquid squeezing roller 92 is pressed into the liquid coating roller 1 or separate the liquid coating roller 1 from the liquid squeezing roller 92.
As can be seen from the above, in the chain-type roller coating apparatus of the present disclosure, the spacing between the liquid coating roller 1 and the liquid squeezing roller 92 can be adjusted, the degree by which the liquid squeezing roller 92 is pressed into the liquid coating roller 1 can be controlled, and the separation of the liquid coating roller 1 from the liquid squeezing roller 92 can also be realized, to avoid the serious deformation of the liquid coating roller 1 due to the liquid coating roller 1 still being in the local squeezed state after shutdown, thereby prolonging the service life of the liquid coating roller 1, and ensuring the roller coating effect.
The chain-type roller coating apparatus of the present disclosure is applicable to a chain-type diffusion process, a chain-type gettering process, or a laser-doped selective emitter (SE) process, and the chain-type roller coating apparatus is suitable for producing TOPCon cells or HJT cells, and realizes a fully automated production line, thereby improving the production efficiency.
While preferred embodiments of the present disclosure have been described above, the present disclosure is not limited thereto. It should be appreciated that some improvements and modifications can be made by those skilled in the art without departing from the technical principles of the present disclosure, which are also contemplated to be within the scope of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202110296523.5 | Mar 2021 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/118305 | 9/14/2021 | WO |
