Monocrystalline silicon battery piece wet etching device, production process and solar battery piece

Abstract

The invention relates to a monocrystalline silicon battery piece wet etching device, a production process and a solar battery piece, the device comprises an etching groove, a plurality of transmission rollers are rotatably arranged in the etching groove, and the etching groove is further internally provided with a transmission cylinder, a plurality of transmission rollers and a plurality of transmission rollers, the adjusting roller is arranged in the conveying cylinder; the synchronous transmission structure is used for realizing meshing transmission between the transmission roller and the transmission cylinder and meshing transmission between the transmission cylinder and the adjusting roller; one end of the swing arm is rotationally mounted at the end of the conveying roller, and the other end of the swing arm is rotationally connected with the end of the adjusting roller, so that the conveying cylinder always keeps a simultaneous meshing state with the adjusting roller and the conveying roller; and the inclination adjusting mechanism is used for enabling the swing arm to swing back and forth at a set angle when the conveying roller rotates continuously, so that the vertical height of the highest position of the arc-surface peripheral wall of the conveying barrel is intermittently increased or decreased. According to the application, the silicon wafer can advance in an inclined state in the transmission process, so that the etching liquid on the surface of the silicon wafer is stronger in flowability, and the etching uniformity of the silicon wafer is improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor wet etching, and in particular to a single crystal silicon cell wet etching device and production process, and a solar cell. Background Art

[0002] At present, the production of monocrystalline silicon cells mainly includes the following steps: texturing, diffusion, etching, anti-reflection film coating, electrode printing, and electrode sintering. There are currently two main etching methods, namely dry etching and wet etching. Among them, wet etching is to use the chemical reaction between the corrosive liquid and the part to be removed to etch, and the main purpose is to remove the redundant PN junction on the back and edge of the silicon wafer, as well as the PSG layer on the front.

[0003] In the related art, the Chinese patent with application number CN202311113227.2 proposes a wet etching device for avoiding top Mo indentation. The wet etching device is provided with a dry interval, an etching interval, a buffer interval, a water washing interval and an air drying interval in sequence according to the transmission direction of the substrate; a first magnet device is provided in the etching interval, and a second magnet device is also provided in the buffer interval. The wet etching device also includes a vortex tube, and a hot air outlet and a first exhaust port are also provided in the buffer interval. The shape of the buffer air knife is set in an arc shape, and a hot air pipe is provided obliquely above the buffer air knife. The nozzle of the hot air pipe is directly opposite to the buffer air knife, and the hot air branch of the vortex tube is connected to the hot air outlet and the hot air pipe respectively; the wet etching device also includes a cooling device, and the cold air branch of the vortex tube is connected to the cooling device. This invention can effectively avoid the top Mo indentation problem in the Mo / Al and Mo / Al / Mo etching processes, avoid quality problems such as display stains, and ensure product quality and yield.

[0004] The above-mentioned related technologies have the following defects: when the silicon wafer passes through the etching groove, the etching solution in the etching groove continuously etches the surface of the silicon wafer, but as the area of ​​the silicon wafer increases, the replaceability of the solution in the middle of the silicon wafer and on the side away from the moving direction of the silicon wafer becomes worse, so that an etching solution concentration gradient is generated on the surface of the silicon wafer during the etching process, which affects the etching uniformity of the silicon wafer; the current existing technology uses inclined etching to improve this phenomenon, but too large an inclination angle may cause the etching solution to be lost too quickly, and too small an inclination angle may not be enough to improve the replaceability of the solution, and the inclination angle cannot be continuously adjusted; and when used in batch wet etching production of silicon wafers, it is difficult to apply it in large quantities due to the limitation of the control accuracy of the inclination angle and the corrosion effect of the etching solution. Summary of the invention

[0005] In order to improve the problem that it is difficult to accurately control the tilt angle of tilted etching of large quantities of silicon wafers during wet etching and it is difficult to continuously produce in large quantities, the present application provides a single crystal silicon cell wet etching device and production process, and a solar cell.

[0006] The first aspect of the present application provides a single crystal silicon cell wet etching device using the following technical solution: A monocrystalline silicon cell wet etching device comprises an etching tank, in which a plurality of transmission rollers are rotatably arranged, and a driving mechanism for driving the plurality of transmission rollers to rotate in the same direction and at the same speed is arranged in the etching tank, and the etching tank is also provided with: A transmission cylinder, which is sleeved on the outer circumference of the transmission roller and is used to transmit the silicon wafer during rotation, and the axis of the transmission cylinder is parallel to the axis of the transmission roller; An adjusting roller is arranged in the transmission cylinder, the axis of the adjusting roller is parallel to the axis of the transmission roller and the line connecting the axes of the two passes through the axis of the transmission cylinder; A synchronous transmission structure, used to realize the meshing transmission between the transmission roller and the transmission cylinder, and to realize the meshing transmission between the transmission cylinder and the adjustment roller; A swing arm, one end of which is rotatably mounted on the end of the transmission roller and the other end of which is rotatably connected to the end of the adjustment roller, so as to ensure that the transmission cylinder always maintains a simultaneous meshing state with the adjustment roller and the transmission roller; and A tilt adjustment mechanism, used to enable the swing arm to swing back and forth at a set angle when the transmission roller rotates continuously, so that the vertical height of the highest point of the outer peripheral wall of the arc surface of the transmission cylinder is intermittently increased or decreased; The etching liquid level in the etching groove is higher than the highest point of the outer peripheral wall of the arc surface of the transmission tube.

[0007] Furthermore, the synchronous transmission structure includes: A first inner gear ring, coaxially fixed to the inner circumferential wall of the transmission cylinder; A first outer gear ring, coaxially fixed to the outer peripheral wall of the transmission roller; and A second outer gear ring, coaxially fixed to the outer peripheral wall of the adjusting roller; The first outer gear ring and the second outer gear ring are both meshingly connected with the first inner gear ring.

[0008] Furthermore, at least one anti-slip ring located on the end surface of the first inner gear ring is fixedly connected to the inner circumferential wall of the transmission cylinder.

[0009] Furthermore, the tilting mechanism comprises: An inner tooth arc strip is coaxially mounted on the end surface of the transmission roller; An outer tooth arc bar is fixedly connected to one end of the swing arm close to the transmission roller, and the axis of the outer tooth arc bar is colinear with the swing axis of the swing arm; and A reversing gear is rotatably mounted on the etching groove, the reversing gear is meshed and connected with the outer tooth arc strip, and when the transmission roller rotates until the inner tooth arc strip corresponds to the reversing gear, the ring gear is also meshed and connected with the inner tooth arc strip; When the transmission roller rotates to the point where the end of the inner tooth arc strip deviates from its rotation direction and is about to be disengaged from the reversing gear, the swing arm flips over until the axis of the adjustment roller is coplanar with the axis of the transmission roller.

[0010] Furthermore, a support frame is installed at the end of the etched groove close to the transmission roller, and a rotating shaft is coaxially fixed to the end of the transmission roller. The reversing gear and the rotating shaft are both rotatably installed on the support frame, and one end of the swing arm close to the transmission roller is gap-mounted on the outer periphery of the rotating shaft and rotatably installed on the support frame.

[0011] Furthermore, a torsion elastic member is provided between the support frame and the swing arm and is sleeved on the outer circumference of the rotating shaft with a gap, and one end of the torsion elastic member is connected to the support frame, and the other end is connected to the swing arm; When the torsion elastic member is in an initial state, the swing arm flips over until the adjusting roller is located directly below the transmission roller.

[0012] Furthermore, at least two of the transmission rollers in the etching groove form a transmission group, and when the transmission rollers in the same transmission group rotate, the corresponding adjustment rollers are located in the same position; In two adjacent transmission groups, when the adjustment roller in one of the transmission groups is located directly below the corresponding transmission roller, the axis of the adjustment roller in the other transmission group is horizontally coplanar with the axis of the corresponding transmission roller.

[0013] Furthermore, the inner tooth arc strip is detachably mounted on the end surface of the transmission roller, and a locking structure for locking the swing arm at a set position is provided on the support frame.

[0014] The second aspect of the present application provides a single crystal silicon cell wet etching production process using the following technical solution: A single crystal silicon cell wet etching production process, based on the above-mentioned single crystal silicon cell wet etching device, comprises the following steps: S1. The batch of silicon wafers are sequentially flattened and transported to the plurality of the transfer cylinders in the etching tank, and the liquid level of the etching solution in the etching tank is controlled to be higher than the upper surface of the silicon wafer on the transfer cylinder; S2. The plurality of transfer rollers are driven to rotate by the driving mechanism, and when the transfer rollers rotate, the transfer cylinders meshing therewith are driven to rotate to transfer the silicon wafers, so that the batch of silicon wafers travels through the etching liquid in the etching groove to complete the wet etching; S3. During the rotation of the transmission roller, the swing arm is driven to swing back and forth by means of the tilt adjustment mechanism, so that the vertical height of the highest point of the outer peripheral wall of the arc surface of the transmission cylinder is intermittently increased or decreased, so that the silicon wafer is tilted and flipped within the set tilt angle range during the process of passing through the etching liquid; S4. After etching is completed, water washing, alkali washing, water washing, acid washing, water washing and drying are carried out in sequence.

[0015] A third aspect of the present application provides a solar cell adopting the following technical solution: A solar cell is manufactured based on the above-mentioned single crystal silicon cell wet etching production process.

[0016] In summary, the beneficial technical effects of this application are: 1. The swing arm is used to limit the distance between the adjusting roller and the transmission roller, so that the axes of the adjusting roller and the transmission roller are always on both sides of the axis of the transmission cylinder. When the swing arm is flipped to any angle, the transmission cylinder always maintains the simultaneous meshing state with the adjusting roller and the transmission roller, which can ensure the stable rotation of the transmission cylinder to smoothly transport the silicon wafers; 2. During the continuous rotation of the transmission roller, when the inner tooth arc bar rotates to mesh with the reversing gear and disengages from the reversing gear, the swing arm can drive the adjusting roller to swing back and forth at a set angle with the axis of the transmission roller as the rotation axis, so that the straight-line distance from the highest point of the outer peripheral wall of the arc surface of the transmission cylinder to the highest point of the outer peripheral wall of the arc surface of the transmission cylinder to the highest point of the arc surface of the transmission roller gradually increases, which can change the vertical height of the corresponding part of the silicon wafer carried on the transmission cylinder; on the one hand, the silicon wafer can be moved in an inclined state during the transmission process, so that the etching solution on the surface of the silicon wafer has stronger fluidity, which helps to reduce the concentration gradient of the etching solution on the surface of the silicon wafer and improve the etching uniformity of the silicon wafer; on the other hand, because the vertical height of the highest point of the outer peripheral wall of the arc surface of the transmission cylinder increases smoothly during the swing arm swinging, the disturbance effect of the silicon wafer on the etching solution during the dynamic change of the tilt angle can be effectively reduced, and the flow uniformity of the etching solution on the inclined silicon wafer surface can be ensured to avoid the problem of uneven etching; 3. By organizing at least two transmission rollers into a transmission group and making the movement states of multiple adjustment rollers in the same transmission group the same, the silicon wafer can move more smoothly within a certain period of time after the tilt angle is adjusted when being transmitted on the transmission cylinder, which can effectively avoid the situation where the etching liquid flows too fast due to frequent tilt angle adjustments of the silicon wafer, affecting the etching effect; and by setting the movement states of the adjustment rollers in two adjacent transmission groups to be different, it can be ensured that the silicon wafer can adjust its tilt angle every time it passes through two adjacent transmission groups, so as to promote the replacement of the etching liquid on the surface of the silicon wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application; Figure 2 is a schematic diagram of the overall structure when the axis of the adjustment roller and the axis of the transmission roller are in the same horizontal plane in the embodiment of the present application; Figure 3 is a schematic diagram of the overall structure when the adjustment roller of the embodiment of the present application is located directly below the transmission roller; Figure 4 : is a comparison diagram of the front and rear states of the swing arm of the embodiment of the present application when it is flipped 90°; Figure 5 It is a schematic cross-sectional structure diagram mainly used to show the torsion elastic member in the embodiment of the present application; Figure 6 is a schematic diagram of the overall structure when two inner tooth arc strips are provided in the embodiment of the present application; Figure 7 It is a schematic diagram of the overall structure when the inner tooth arc strip of the embodiment of the present application is detachably arranged.

[0018] Description of reference numerals: 1. Etching grooves; 2. Transmission roller; 21. First outer gear ring; 22. Inner gear arc strip; 23. Rotating shaft; 241. Mounting ear; 242. Mounting bolt; 3. Transmission cylinder; 31. First inner gear ring; 32. Anti-slip ring; 4. Adjusting roller; 41. Second outer gear ring; 5. Swing arm; 51. External tooth arc strip; 6. Support frame; 61. Reversing gear; 62. Torsion elastic member; 71. locking bolt; 72. arc groove; 8. Silicon wafer. DETAILED DESCRIPTION

[0019] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0020] The present application embodiment discloses a single crystal silicon cell wet etching device. Figure 1 , Figure 2 and Figure 3It includes a long strip-shaped etching groove 1, in which a plurality of mutually parallel transmission rollers 2 are rotatably arranged, and the plurality of transmission rollers 2 are arranged in sequence and at equal intervals along the length direction of the etching groove 1. A driving mechanism for driving the plurality of transmission rollers 2 to rotate in the same direction and at the same speed is provided in the etching groove 1, wherein the driving mechanism is a conventional technical means and will not be described in detail here.

[0021] The etching tank 1 is also provided with: The transmission cylinder 3 is sleeved on the outer circumference of the transmission roller 2 and is used to transmit the silicon wafer 8 during rotation. The axis of the transmission cylinder 3 is parallel to the axis of the transmission roller 2.

[0022] The adjusting roller 4 is arranged in the transmission cylinder 3, the axis of the adjusting roller 4 is parallel to the axis of the transmission roller 2, and the line connecting the two axes passes through the axis of the transmission cylinder 3, and the adjusting roller 4 and the transmission roller 2 are arranged with a gap.

[0023] The synchronous transmission structure is used to realize the meshing transmission between the transmission roller 2 and the transmission cylinder 3, and to realize the meshing transmission between the transmission cylinder 3 and the adjusting roller 4.

[0024] The swing arm 5 has one end rotatably mounted on the end of the transmission roller 2 and the other end rotatably connected to the end of the adjustment roller 4, so as to keep the transmission cylinder 3 always in meshing state with the adjustment roller 4 and the transmission roller 2, so as to ensure that the transmission roller 2 can stably drive the transmission cylinder 3 meshed with it to rotate when rotating. The tilting mechanism is used to make the swing arm 5 swing back and forth at a set angle when the transmission roller 2 rotates continuously, so that the vertical height of the highest point of the arc surface outer peripheral wall of the transmission cylinder 3 increases or decreases intermittently; Moreover, the liquid level of the etching solution in the etching groove 1 is higher than the highest point of the arc-surface outer peripheral wall of the transmission tube 3 .

[0025] In the specific settings, refer to Figure 1 , at least two transmission rollers 2 in the etching groove 1 form a transmission group, and when the transmission rollers 2 in the same transmission group rotate, the corresponding adjustment rollers 4 are in the same position; In two adjacent transmission groups, when the adjustment roller 4 in one of the transmission groups is located directly below the corresponding transmission roller 2, the axis of the adjustment roller 4 in the other transmission group is horizontally coplanar with the axis of the corresponding transmission roller 2.

[0026] Therefore, when the silicon wafer 8 travels through the etching liquid in the etching groove 1, the driving mechanism drives the multiple transmission rollers 2 to rotate synchronously. When the transmission rollers 2 rotate, the transmission drum 3 keeps rotating in the same direction with the transmission rollers 2 by means of the synchronous transmission structure, and the swing arm 5 limits the distance between the adjusting roller 4 and the transmission roller 2, so that the axes of the adjusting roller 4 and the transmission roller 2 are always arranged on both sides of the axis of the transmission drum 3, so that no matter when the swing arm 5 is flipped to any angle, the transmission drum 3 always keeps a simultaneous meshing state with the adjusting roller 4 and the transmission roller 2, which can ensure the stable rotation of the transmission drum 3 to smoothly transport the silicon wafer 8.

[0027] When the transmission roller 2 is in the process of continuous rotation, with the help of the setting of the tilting mechanism, the swing arm 5 can drive the adjusting roller 4 to swing back and forth at a set angle with the axis of the transmission roller 2 as the rotation axis 23. For example, taking the set maximum swing angle of the swing arm 5 as 90°, when the swing arm 5 swings to the point where the adjusting roller 4 is directly below the transmission roller 2, assuming that the adjusting roller 4 is in the initial position at this time, the highest point of the arc-surface outer wall of the transmission cylinder 3 is closest to the highest point of the arc-surface outer wall of the transmission roller 2, which means that the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 is at the lowest point, such as Figure 4 -b; and as the transmission roller 2 continues to rotate, the swing arm 5 gradually swings until the axis of the adjustment roller 4 and the axis of the transmission cylinder 3 are in the same horizontal plane, and the swing angle of the swing arm 5 reaches 90°. At this time, the straight-line distance between the highest point of the outer peripheral wall of the arc surface of the transmission cylinder 3 and the highest point of the arc surface of the transmission roller 2 gradually increases, indicating that the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 is gradually lifted to the highest point, as shown in FIG. Figure 4 -a as shown.

[0028] Thus, on the one hand, the silicon wafer 8 can be moved in an inclined state during the transmission process, so that the etching solution on the surface of the silicon wafer 8 has stronger fluidity, which helps to reduce the concentration gradient of the etching solution on the surface of the silicon wafer 8 and improve the etching uniformity of the silicon wafer 8; on the other hand, since the vertical height of the highest point of the arc-surface outer wall of the transmission cylinder 3 increases smoothly during the swinging of the swing arm 5, the disturbance effect of the silicon wafer 8 on the etching solution during the dynamic change of the tilt angle can be effectively reduced, and the flow uniformity of the etching solution on the inclined surface of the silicon wafer 8 can be ensured to avoid the problem of uneven etching.

[0029] By grouping at least two transmission rollers 2 into a transmission group and making the motion states of multiple adjustment rollers 4 in the same transmission group the same, the silicon wafer 8 can be transported on the transmission cylinder 3 and can move relatively smoothly within a certain period of time after the tilt angle is adjusted, which can effectively avoid the situation where the etching liquid flows too fast due to frequent tilt angle adjustments of the silicon wafer 8, affecting the etching effect. By setting the motion states of the adjustment rollers 4 in two adjacent transmission groups to be different, it can be ensured that the silicon wafer 8 can adjust its tilt angle every time it passes through two adjacent transmission groups, so as to promote the replacement of the etching liquid on the surface of the silicon wafer 8.

[0030] Specifically, refer to Figure 2 , the synchronous transmission structure includes: The first inner gear ring 31 is coaxially fixed to the inner circumferential wall of the transmission cylinder 3; A first outer gear ring 21 is coaxially fixed to the outer peripheral wall of the transmission roller 2; and The second outer gear ring 41 is coaxially fixed to the outer peripheral wall of the adjusting roller 4; The first outer gear ring 21 and the second outer gear ring 41 are meshed and connected with the first inner gear ring 31, and at least one anti-slip ring 32 located on the end face of the first inner gear ring 31 is fixedly connected to the inner circumferential wall of the transmission cylinder 3. In the specific configuration, the first inner gear ring 31 is provided at both ends of the transmission cylinder 3, the first outer gear ring 21 is provided at both ends of the transmission roller 2, and the second outer gear ring 41 is provided at both ends of the adjustment roller 4, so the anti-slip ring 32 can be provided with two at only one end of the transmission cylinder 3, or one or two can be provided at both ends of the transmission cylinder 3.

[0031] Therefore, when the transmission roller 2 rotates under the drive of the driving mechanism, it drives the transmission cylinder 3 to rotate synchronously through the meshing connection between the first outer gear ring 21 and the first inner gear ring 31, so as to realize the effective transmission of the silicon wafer 8 by the transmission cylinder 3; and the meshing of the second outer gear ring 41 and the first inner gear ring 31 ensures that when the swing arm 5 drives the adjusting roller 4 to move forward or reverse relative to the transmission cylinder 3 during swinging, it will not interfere with the normal rotation of the transmission cylinder 3, and at the same time ensure the smooth rotation of the transmission cylinder 3; the setting of the anti-slip ring 32 ensures that the first inner gear ring 31 is always in meshing state with the first outer gear ring 21 and the second outer gear ring 41 to avoid their disengagement during the meshing transmission process.

[0032] Further, see Figure 2 and Figure 3 The above-mentioned tilting mechanism includes: The inner tooth arc strip 22 is coaxially mounted on the end surface of the transmission roller 2, and corresponds to the aforementioned maximum swing angle of the swing arm 5 being set to 90°. In this embodiment, the inner tooth arc strip 22 is a quarter arc; The outer tooth arc strip 51 is fixedly connected to one end of the swing arm 5 close to the transmission roller 2, and the axis of the outer tooth arc strip 51 is colinear with the swing axis of the swing arm 5; and The reversing gear 61 is rotatably mounted on the etching groove 1, the reversing gear 61 is meshed and connected with the outer tooth arc strip 51, and when the transmission roller 2 rotates until the inner tooth arc strip 22 corresponds to the reversing gear 61, the ring gear is also meshed and connected with the inner tooth arc strip 22; When the transmission roller 2 rotates until the end of the inner tooth arc 22 deviates from its rotation direction and is about to be disengaged from the reversing gear 61, the swing arm 5 flips until the axis of the adjustment roller 4 is horizontally coplanar with the axis of the transmission roller 2.

[0033] Specifically, a support frame 6 is installed at the end of the etching groove 1 close to the transmission roller 2, and a rotating shaft 23 is coaxially fixed to the end of the transmission roller 2, and a driving mechanism is used to drive the rotating shaft 23 to rotate; the reversing gear 61 and the rotating shaft 23 are both rotatably installed on the support frame 6, and one end of the swing arm 5 close to the transmission roller 2 is gap-mounted on the outer periphery of the rotating shaft 23 and rotatably installed on the support frame 6.

[0034] And, refer to Figure 5A torsion elastic member 62 is provided between the support frame 6 and the swing arm 5 and is sleeved on the outer periphery of the rotating shaft 23. One end of the torsion elastic member 62 is connected to the support frame 6, and the other end is connected to the swing arm 5. The torsion elastic member 62 is configured as a torsion spring, and the torsion elastic member 62 is made of a polymer plastic such as PTFE, PEEK, PVDF, PPS, etc. that is resistant to acid and alkali corrosion and has good mechanical properties; When the torsion elastic member 62 is in the initial state, the swing arm 5 flips over until the adjustment roller 4 is located directly below the transmission roller 2 .

[0035] Therefore, when the adjusting roller 4 on the swing arm 5 is in the aforementioned initial position, the corresponding part of the silicon wafer 8 carried by the transmission cylinder 3 is at the lowest point. At this time, the reversing gear 61 does not contact the inner tooth arc strip 22 on the transmission roller 2. Figure 4 -b. As the transmission roller 2 rotates, for example, clockwise, it drives the inner tooth arc strip 22 to rotate clockwise, and also drives the transmission cylinder 3 meshed with it to rotate clockwise; when the inner tooth arc strip 22 rotates to mesh with the reversing gear 61, as the transmission roller 2 continues to rotate, the inner tooth arc strip 22 drives the reversing gear 61 to rotate clockwise, and the reversing gear 61 drives the outer tooth arc strip 51 meshed with it to drive the swing arm 5 to swing counterclockwise on the support frame 6, until the inner tooth arc strip 22 is about to disengage from the reversing gear 61, as shown in FIG. Figure 4 -a, the swing arm 5 is flipped until the axis of the adjustment roller 4 is coplanar with the axis of the transmission roller 2, so that the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 is at the highest point, and the gentle tilt angle adjustment of the silicon wafer 8 can be achieved.

[0036] After the swing arm 5 is flipped, the torsional elastic member 62 is twisted to produce torsional deformation. Therefore, when the transmission roller 2 continues to rotate, the inner tooth arc bar 22 is completely disengaged from the reversing gear 61, and the swing arm 5 will swing in the clockwise direction under the action of the torsional deformation force of the torsional elastic member 62. Then, by adjusting the engagement between the roller 4 and the transmission cylinder 3, the transmission cylinder 3 can maintain a stable clockwise rotation while the vertical height of the highest point of the arc-surface outer wall is also reduced, so that the inclination angle of the silicon wafer 8 carried thereon can be adjusted.

[0037] However, considering that the swing arm 5 will encounter resistance from the etching liquid when swinging clockwise under the deformation force of the torsional elastic member 62, thereby reducing the rotation speed of the swing arm 5, there is still a possibility that the vertical height of the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 will drop too quickly, which may cause turbulence of the etching liquid on the surface of the silicon wafer 8 or the position of the silicon wafer 8 on the transmission cylinder 3. Therefore, in another feasible embodiment, an acid- and alkali-resistant damping rubber ring (not shown in the figure) may be provided between the swing arm 5 and the support frame 6 to reduce the rotation speed of the swing arm 5 so that the vertical height of the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 drops more slowly.

[0038] In addition, further considering that based on the setting of the above-mentioned inner tooth arc bar 22 as a quarter arc, during the process of the transmission roller 2 rotating one circle, the time when the vertical height of the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 is in an upward state is one third of the time when the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 is at the lowest point. It is possible that when the silicon wafer 8 crosses two adjacent transmission groups, the highest points of the outer arc surfaces of the transmission cylinders 3 in the two transmission groups are in the lowest state, so that the silicon wafer 8 cannot adjust the tilt angle when passing through the two transmission groups.

[0039] To this end, in another possible embodiment, refer to Figure 6 , two inner tooth arc strips 22 of a quarter arc are set and distributed in a circular array with equal spacing along the axis of the transmission roller 2. This ensures that the transmission cylinders 3 in two adjacent transmission groups are always in different states, so as to ensure the smooth adjustment of the tilt angle of the silicon wafer 8.

[0040] At the same time, considering that different etching solutions have different requirements for oblique etching, the etching device of the present application is suitable for different etching requirements.

[0041] In other possible embodiments, refer to Figure 7 The inner tooth arc strip 22 can be detachably mounted on the end surface of the transmission roller 2, and a locking structure for locking the swing arm 5 at a set position is provided on the support frame 6. Specifically, both ends of the inner tooth arc strip 22 are fixedly connected with mounting ears 241, and the mounting ears 241 are penetrated with mounting bolts 242 threadedly connected to the end surface of the transmission roller 2; the locking structure includes a plurality of locking bolts 71 threadedly connected to the swing arm 5, and an arc groove 72 whose axis is colinear with the swing axis of the swing arm 5 is opened on the support frame 6, and the locking bolts 71 are penetrated in the arc groove 72.

[0042] In this way, when there is no need to perform oblique etching on the silicon wafer 8 during the transmission of the silicon wafer 8, the mounting bolt 242 can be unscrewed and the inner tooth arc bar 22 can be removed. At the same time, the swing arm 5 can be swung to a suitable position, and the locking bolt 71 can be passed through the arc groove 72 and screwed on the swing arm 5. The locking bolt 71 can be tightened to fix the swing arm 5. The present application can realize flexible switching among different wet etching processes, which greatly expands the application scope of the present application.

[0043] In addition, all components of the wet etching device of the present application are made of polymer plastics that are resistant to acid and alkali corrosion, such as PEEK, PVDF, PPS, PC, etc.

[0044] The present application embodiment discloses a single crystal silicon cell wet etching production process, based on the above-mentioned single crystal silicon cell wet etching device, referring to Figure 1 , which comprises the following steps: S1. The batch of silicon wafers 8 are sequentially flattened and transported to the plurality of transmission cylinders 3 in the etching tank 1, and the liquid level of the etching solution in the etching tank 1 is controlled to be higher than the upper surface of the silicon wafer 8 on the transmission cylinder 3; S2. The plurality of transmission rollers 2 are driven to rotate by a driving mechanism, and when the transmission rollers 2 rotate, the transmission cylinders 3 meshing therewith are driven to rotate to transmit the silicon wafers 8, so that the batch of silicon wafers 8 travels through the etching liquid in the etching groove 1 to complete the wet etching; S3. During the rotation process, the transmission roller 2 drives the swing arm 5 to swing back and forth by means of the tilt adjustment mechanism, so that the vertical height of the highest point of the outer peripheral wall of the arc surface of the transmission cylinder 3 is intermittently increased or decreased, so that the silicon wafer 8 is tilted and flipped within the set tilt angle range during the process of passing through the etching liquid; S4. After etching is completed, water washing, alkali washing, water washing, acid washing, water washing and drying are carried out in sequence.

[0045] The embodiment of the present application discloses a solar cell, which is processed by the above-mentioned single crystal silicon cell wet etching production process.

[0046] The implementation principle of a single crystal silicon cell wet etching device in the embodiment of the present application is as follows: The swing arm 5 is used to limit the distance between the adjustment roller 4 and the transmission roller 2, so that the axes of the adjustment roller 4 and the transmission roller 2 are always arranged on both sides of the axis of the transmission cylinder 3, so that when the swing arm 5 is flipped to any angle, the transmission cylinder 3 always maintains a simultaneous meshing state with the adjustment roller 4 and the transmission roller 2, which can ensure the stable rotation of the transmission cylinder 3 to smoothly transport the silicon wafer 8. Therefore, when the transmission roller 2 is in the process of continuous rotation, when the inner tooth arc bar 22 rotates and meshes with the reversing gear 61 and disengages from the reversing gear 61, the swing arm 5 can drive the adjustment roller 4 to swing back and forth at a set angle with the axis of the transmission roller 2 as the rotation axis 23, so that the highest point of the arc surface outer peripheral wall of the transmission cylinder 3 is gradually increased from the highest point of the arc surface outer peripheral wall closest to the transmission roller 2 to the highest point of the arc surface outer peripheral wall of the transmission cylinder 3. The vertical height of the corresponding part of the silicon wafer 8 carried on the transmission cylinder 3 can be changed.

[0047] Thus, on the one hand, the silicon wafer 8 can be moved in an inclined state during the transmission process, so that the etching solution on the surface of the silicon wafer 8 has stronger fluidity, which helps to reduce the concentration gradient of the etching solution on the surface of the silicon wafer 8 and improve the etching uniformity of the silicon wafer 8; on the other hand, since the vertical height of the highest point of the arc-surface outer wall of the transmission cylinder 3 increases smoothly during the swinging of the swing arm 5, the disturbance effect of the silicon wafer 8 on the etching solution during the dynamic change of the tilt angle can be effectively reduced, and the flow uniformity of the etching solution on the inclined surface of the silicon wafer 8 can be ensured to avoid the problem of uneven etching.

[0048] By grouping at least two transmission rollers 2 into a transmission group and making the motion states of multiple adjustment rollers 4 in the same transmission group the same, the silicon wafer 8 can be transported on the transmission cylinder 3 and can move relatively smoothly within a certain period of time after the tilt angle is adjusted, which can effectively avoid the situation where the etching liquid flows too fast due to frequent tilt angle adjustments of the silicon wafer 8, affecting the etching effect. By setting the motion states of the adjustment rollers 4 in two adjacent transmission groups to be different, it can be ensured that the silicon wafer 8 can adjust its tilt angle every time it passes through two adjacent transmission groups, so as to promote the replacement of the etching liquid on the surface of the silicon wafer 8.

[0049] Unless otherwise defined, the technical terms or scientific terms used in this application should be understood by people with ordinary skills in the field to which this application belongs. The words "first", "second", "third" and similar words used in the specification and claims of this application do not indicate any order, quantity or importance, but are only used to distinguish different components. "One" or "one" and similar words do not indicate a quantitative limit, but indicate that there is at least one. "Include" or "comprise" and similar words mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0050] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A single crystal silicon cell wet etching device, comprising an etching tank (1), wherein a plurality of transmission rollers (2) are rotatably arranged in the etching tank (1), and a driving mechanism for driving the plurality of transmission rollers (2) to rotate in the same direction and at the same speed is arranged in the etching tank (1), characterized in that: The etching groove (1) is also provided with: A transmission cylinder (3) is sleeved on the outer circumference of the transmission roller (2) and is used to transmit the silicon wafer (8) during rotation, wherein the axis of the transmission cylinder (3) is parallel to the axis of the transmission roller (2); An adjusting roller (4) is arranged in the transmission cylinder (3), the axis of the adjusting roller (4) is parallel to the axis of the transmission roller (2), and the line connecting the axes of the two passes through the axis of the transmission cylinder (3); A synchronous transmission structure, used to realize meshing transmission between the transmission roller (2) and the transmission cylinder (3), and to realize meshing transmission between the transmission cylinder (3) and the adjustment roller (4); a swing arm (5), one end of which is rotatably mounted on the end of the transmission roller (2) and the other end of which is rotatably connected to the end of the adjustment roller (4), so as to enable the transmission cylinder (3) to always maintain a simultaneous meshing state with the adjustment roller (4) and the transmission roller (2); and A tilt adjustment mechanism, used to enable the swing arm (5) to swing back and forth at a set angle when the transmission roller (2) rotates continuously, so that the vertical height of the highest point of the arc-surface outer peripheral wall of the transmission cylinder (3) increases or decreases intermittently; The level of the etching liquid in the etching groove (1) is higher than the highest point of the arc-surface outer peripheral wall of the transmission tube (3).

2. The single crystal silicon cell wet etching device according to claim 1, characterized in that: The synchronous transmission structure comprises: A first inner gear ring (31) is coaxially fixed to the inner circumferential wall of the transmission cylinder (3); A first outer gear ring (21) is coaxially fixed to the outer peripheral wall of the transmission roller (2); and A second outer gear ring (41) is coaxially fixed to the outer peripheral wall of the adjusting roller (4); The first outer gear ring (21) and the second outer gear ring (41) are both meshingly connected to the first inner gear ring (31).

3. The single crystal silicon cell wet etching device according to claim 2, characterized in that: At least one anti-slip ring (32) located on the end surface of the first inner gear ring (31) is fixedly connected to the inner peripheral wall of the transmission cylinder (3).

4. The single crystal silicon cell wet etching device according to claim 1, characterized in that: The tilting mechanism comprises: An inner tooth arc strip (22) is coaxially mounted on the end surface of the transmission roller (2); An outer tooth arc strip (51) is fixedly connected to one end of the swing arm (5) close to the transmission roller (2), and the axis of the outer tooth arc strip (51) is colinear with the swing axis of the swing arm (5); and a reversing gear (61) rotatably mounted on the etching groove (1), the reversing gear (61) being meshingly connected with the outer tooth arc strip (51), and when the transmission roller (2) rotates until the inner tooth arc strip (22) corresponds to the reversing gear (61), the ring gear is also meshingly connected with the inner tooth arc strip (22); When the transmission roller (2) rotates until the end of the inner tooth arc strip (22) that deviates from its rotation direction is about to be disengaged from the reversing gear (61), the swing arm (5) flips until the axis of the adjustment roller (4) is horizontally coplanar with the axis of the transmission roller (2).

5. The single crystal silicon cell wet etching device according to claim 4, characterized in that: A support frame (6) is installed at the end of the etching groove (1) close to the transmission roller (2), and a rotating shaft (23) is coaxially fixedly connected to the end of the transmission roller (2). The reversing gear (61) and the rotating shaft (23) are both rotatably mounted on the support frame (6), and one end of the swing arm (5) close to the transmission roller (2) is gap-mounted on the outer periphery of the rotating shaft (23) and rotatably mounted on the support frame (6).

6. The single crystal silicon cell wet etching device according to claim 5, characterized in that: A torsion elastic member (62) is provided between the support frame (6) and the swing arm (5) and is sleeved on the outer circumference of the rotating shaft (23) with a gap, and one end of the torsion elastic member (62) is connected to the support frame (6) and the other end is connected to the swing arm (5); When the torsion elastic member (62) is in the initial state, the swing arm (5) flips over until the adjustment roller (4) is located directly below the transmission roller (2).

7. The single crystal silicon cell wet etching device according to any one of claims 1 to 6, characterized in that: At least two of the transmission rollers (2) in the etching groove (1) form a transmission group, and when the transmission rollers (2) in the same transmission group rotate, the corresponding adjustment rollers (4) are located in the same position; In two adjacent transmission groups, when the adjustment roller (4) in one of the transmission groups is located directly below the corresponding transmission roller (2), the axis of the adjustment roller (4) in the other transmission group is horizontally coplanar with the axis of the corresponding transmission roller (2).

8. The single crystal silicon cell wet etching device according to claim 5, characterized in that: The inner tooth arc strip (22) is detachably mounted on the end surface of the transmission roller (2), and a locking structure for locking the swing arm (5) at a set position is provided on the support frame (6).

9. A single crystal silicon cell wet etching production process, based on the single crystal silicon cell wet etching device according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Laying a batch of silicon wafers (8) in turn and conveying them to the plurality of transfer cylinders (3) in the etching tank (1), and controlling the liquid level of the etching solution in the etching tank (1) to be higher than the upper surface of the silicon wafers (8) on the transfer cylinders (3); S2. The plurality of transmission rollers (2) are driven to rotate by the driving mechanism, and when the transmission rollers (2) rotate, the transmission cylinders (3) meshed therewith are driven to rotate to transmit the silicon wafers (8), so that the batch of silicon wafers (8) pass through the etching liquid in the etching groove (1) to complete wet etching; S3. During the rotation process, the transmission roller (2) drives the swing arm (5) to swing back and forth with the aid of the tilt adjustment mechanism, so that the vertical height of the highest point of the arc-surface outer peripheral wall of the transmission cylinder (3) increases or decreases intermittently, thereby causing the silicon wafer (8) to be in an inclined and flipping state within a set tilt angle range during the process of passing through the etching liquid; S4. After etching is completed, water washing, alkali washing, water washing, acid washing, water washing and drying are carried out in sequence.

10. A solar cell, manufactured based on the single crystal silicon cell wet etching production process as claimed in claim 9.

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