CN214688470U

CN214688470U - Solar cell SE distributes printing half tone structure

Info

Publication number: CN214688470U
Application number: CN202120258396.5U
Authority: CN
Inventors: 谈锦彪; 从海泉; 马敏杰; 王鹏; 马擎天
Original assignee: Huansheng Photovoltaic Jiangsu Co Ltd
Current assignee: Huansheng Photovoltaic Jiangsu Co Ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-11-12
Anticipated expiration: 2031-01-29

Abstract

The utility model provides a solar cell SE distribution printing half tone structure, including figure one and figure two, be equipped with a plurality of Mark points in figure one and the figure two respectively, and the circumscribed circle or the circumscribed circle of the Mark point structure in the figure one that sets up adjacently and locate in the figure two the circumscribed circle or the circumscribed circle of the Mark point structure are dislocation clearance setting; and the clearance distance is not less than the sum of the radius of the circumscribed circle or the circumscribed circle of the Mark point structure in the first graph and the radius of the circumscribed circle or the circumscribed circle of the Mark point structure in the second graph. The utility model discloses half tone structure, simple structure is through setting up two-layer printing half tone figure and making the position of Mark point set up for the dislocation clearance promptly to discernment Mark point position's accuracy when guaranteeing the second time printing, with the precision that improves twice printing and stack, thereby guarantee the printing quality, improve the yields, it is that the yields improves to 98.8%.

Description

Solar cell SE distributes printing half tone structure

Technical Field

The utility model belongs to the technical field of solar cell prepares, especially, relate to a solar cell SE distributes printing half tone structure.

Background

The existing Selective Emitter (SE) technology in the market is successfully applied to the PERC battery at present, and the battery efficiency can be effectively improved. The common battery printing technology is an SE distribution printing technology and a conventional step printing technology, and the machine table and the screen plate dot-grabbing figures used by the SE distribution printing technology and the conventional step printing technology are concentric circle dots, such as a novel SE Mark dot pattern structure and a preparation method thereof provided by the Chinese patent publication CN111370391A and a crystal silicon solar battery secondary printing front overprint electrode provided by the Chinese patent publication CN 206148443U. The two screen printing plate structures are all concentric circle superposition grabbing point identification printing, identification of a first alignment grabbing point of distributed printing is easy to confirm, however, when the grabbing point is aligned step by step for the second time, certain offset can be caused due to the fact that the figure of the concentric round point is deformed due to printing slurry of the first printing point, the accuracy of printing alignment can be seriously influenced, and the printing quality is directly influenced.

SUMMERY OF THE UTILITY MODEL

The utility model provides a solar cell SE distributes printing half tone structure has solved among the distribution printing of prior art because the printing of centre of a circle Mark point leads to the printing counterpoint inaccurate, influences the technical problem of printing quality.

In order to solve the technical problem, the utility model discloses a technical scheme is:

a solar cell SE distribution printing screen plate structure comprises a first graph and a second graph, wherein a plurality of Mark points are respectively arranged in the first graph and the second graph, and a circumscribed circle or a circumscribed circle of the Mark point structure in the first graph which is adjacently arranged and a circumscribed circle or a circumscribed circle of the Mark point structure in the second graph are arranged in a staggered clearance mode; and the clearance distance is not less than the sum of the radius of the circumscribed circle or the circumscribed circle of the Mark point structure in the first graph and the radius of the circumscribed circle or the circumscribed circle of the Mark point structure in the second graph.

Furthermore, the number of Mark points in the first graph is the same as that of the Mark points in the second graph, and the number of the Mark points is four.

Further, the first graph is a screen printing plate provided with two main grids; the second graph is a screen printing plate provided with a plurality of fine grids; the main grid and the fine grid are straight lines which are continuously arranged; and the width of the main gate is larger than the maximum width of any Mark point.

Preferably, the Mark point in the first graph and the Mark point in the second graph are both located on the axis of the main grid and are symmetrically arranged.

Preferably, the Mark point close to the outermost end is the Mark point in the first graph or the Mark point in the second graph.

Further, the structure of the Mark point arranged in the first graph is the same as or different from the structure of the Mark point arranged in the second graph.

Preferably, all the Mark points in the first graph have the same structural shape.

Preferably, all the Mark points in the second graph have the same structural shape.

Further, the Mark points are structures formed by circles, crosses, squares or other regular polygons.

Preferably, the maximum width of all Mark point structures is not more than 10 mm.

Adopt the utility model relates to a solar cell SE distributes printing half tone structure, through setting up two-layer printing half tone figure and make the position that Mark point set up for the dislocation clearance to discernment Mark point position's accuracy when guaranteeing the printing of second time, with the precision that improves twice printing and stack, thereby guarantee printing quality, improve the yields, it is 98.8% that the yields improves.

Drawings

Fig. 1 is a schematic structural diagram of a solar cell SE distribution printing screen structure according to a first embodiment of the present invention;

fig. 2 is an enlarged view of a portion a according to a first embodiment of the present invention;

fig. 3 is a schematic structural diagram of a solar cell SE distribution printing screen structure according to a second embodiment of the present invention;

fig. 4 is an enlarged view of a portion B according to a second embodiment of the present invention;

fig. 5 is a schematic structural view of a solar cell SE distribution printing screen structure according to a third embodiment of the present invention;

fig. 6 is an enlarged view of a portion C of a third embodiment of the present invention;

fig. 7 is a schematic structural diagram of a solar cell SE distribution printing screen structure according to a fourth embodiment of the present invention;

fig. 8 is an enlarged view of a portion D according to a fourth embodiment of the present invention.

In the figure:

10. a first pattern 11, a main grid 12 and a first Mark point

20. A second pattern 21, a fine grid 22 and a second Mark point

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Example one:

the embodiment provides a solar cell SE distribution printing screen structure, as shown in fig. 1-2, which includes a screen having two patterns 10 of a main grid 11 and a screen having two patterns 20 of a plurality of fine grids 21, where the main grid 11 and the fine grids 21 are both straight lines which are continuously arranged; the pitch of the main gates 11, and the pitch between the fine gates 21 may be determined according to actual circumstances, and is not particularly limited herein. The first pattern 10 and the second pattern 20 have the same outer dimension, the main grids 11 are arranged perpendicular to the fine grids 21, and the main grids 11 are symmetrically arranged.

The first graph 10 and the second graph 20 are respectively provided with a plurality of Mark points one 12 and Mark points two 22, and in this embodiment, the number of the Mark points one 12 in the first graph 10 is the same as the number of the Mark points two 22 in the second graph 20, and the number of the Mark points two 22 is four.

As shown in fig. 1, four Mark points one 12 are respectively arranged close to four corners of the graph one 10, are located on the axis of the main grid 11, and are symmetrically arranged, that is, each main grid 11 is provided with two Mark points one 12, and each end is provided with one Mark point one 12; the purpose is to ensure that all the viewing angles in the layer one 10 can be identified at the same time, and the positions of all the Mark points one 12 can be accurately and simply calculated.

And four Mark points two 22 in the graph two 20 are symmetrically arranged in each end portion of the four orientations and are arranged correspondingly to the two main grids 11 while being arranged adjacent to the four Mark points one 12. Meanwhile, the width of the main gate 11 is larger than the maximum width of any Mark point, i.e., all Mark points are located within the width of the main gate 11. The purpose of being arranged in the main grid 11 is to ensure easy positioning of the identification position thereof, and also to improve the appearance of the whole cell because the main grid 11 is shielded by solder strips or stacked by the stack during the assembly of the stack tiles.

Further, the four Mark points one 12 have a circular structure, and all the Mark points one 12 on the same graph one 10 have the same structure. The four Mark points two 22 on the graph two 20 are all in a cross-shaped structure. And the diameter of the circle of the first Mark point 12 structure in the first graph 10 and the diameter of the circumscribed circle of the second Mark point 22 structure in the second graph 20 which are adjacently arranged are the same and are not more than 10 mm.

Preferably, as shown in fig. 2, the Mark point one 12 and the Mark point two 22 which are adjacently arranged are arranged in a staggered gap manner, and the distance between two circle centers of a circle where the Mark point one 12 is located and a circumscribed circle of the Mark point two 22 is greater than the sum of the radii of the two circles. And the Mark point close to the outermost end in each main gate 11 is the first Mark point 12 in the graph a 10, i.e. two Mark points two 22 are both located between the two first Mark points 12. The Mark points of different graphic layers arranged in a staggered clearance way can ensure that each Mark point is accurately identified and does not have identification deviation when each graphic layer is printed; the identification of the Mark point I12 and the Mark point II 22 of the two groups of graphs can be completed without using a more accurate camera, so that the accurate overlapping and corresponding arrangement of the upper and lower positions of the graph I10 and the graph II 20 is ensured; meanwhile, the bad problem that the position of the second pattern 20 is mistakenly placed due to the fact that Mark point identification is mistaken to cause printing of the fine grid 21 can be solved, the printing quality and the yield are improved, and the utilization rate of silver paste can also be improved.

Example two:

as shown in fig. 3 to 4, the greatest difference between the second embodiment and the first embodiment is that the Mark point close to the outermost end in each main gate 11 is the second Mark point 22 in the graph two 20, i.e., two Mark points two 22 are located outside two Mark points one 12. And the gap distance between the adjacent first Mark point 12 and the second Mark point 22 is still unchanged. The shape of the first Mark point 12 is still a circular structure, the shape of the second Mark point 22 is still a cross-shaped structure, and the diameter of the first Mark point 12 is the same as the diameter of the circumscribed circle of the second Mark point 22. In this embodiment, it is also ensured that the Mark point one 12 in the first graph 10 and the Mark point two 22 in the second graph 20 can be recognized by the cameras respectively, and no position deviation occurs, and the Mark points can be captured quickly and accurately, thereby ensuring that the first graph 10 and the second graph 20 are accurately stacked.

Example three:

as shown in fig. 5-6, the biggest difference between the third embodiment and the first embodiment is that the shape of the Mark point one 12 in the graph one 10 is a square structure, and the shape of the Mark point two 22 in the graph two 20 is a circular structure. The Mark point I12 and the Mark point II 22 with different structures are easier to recognize, and when the Mark point II 22 in the graph II 20 is printed, the recognition of the Mark point II 22 in the graph II 20 is not influenced by the printing effect of the Mark point I12 in the graph I10, so that the upper graph and the lower graph are accurately aligned without recognition deviation, the Mark point I12 in the graph I10 and the Mark point II 22 in the graph II 20 can be quickly and accurately captured, and the printing quality is ensured.

Example four:

as shown in fig. 7 to 8, the biggest difference between the fourth embodiment and the first embodiment is that the shape of the Mark point one 12 in the first graph 10 and the shape of the Mark point two 22 in the second graph 20 are both circular structures. The position distribution of the first Mark point 12 and the second Mark point 22 on the same main grating 11 is not changed, that is, the first Mark point 12 and the second Mark point 22 which are adjacently arranged are still arranged in a dislocation gap.

A solar cell SE distribution printing method adopts the screen structure as described in any one of the above, and comprises the following steps:

firstly: and executing a graph I10 on the front surface of the silicon wafer by adopting laser, firstly printing a screen printing plate layer with a main grid 11, and simultaneously ensuring that four Mark points I12 are respectively arranged close to four corners of the graph I10, are positioned on the axis of the main grid 11 and are symmetrically arranged. The first pattern 10 is printed to obtain the main grid 11, and then the second pattern 20 is printed to obtain the fine grid 21, so as to ensure the width and height of the fine grid 21, ensure all the features of the fine grid 21, and avoid being collapsed, so as to prevent the conversion efficiency of the battery from being affected.

In the printing process, the selective emitter is heavily doped at the contact part of the metal grid line (electrode) and the silicon wafer, and lightly doped at the position between the electrodes. The structure can reduce the recombination of the diffusion layer, thereby improving the short-wave response of light, reducing the contact resistance of the front metal electrode and silicon, better improving the short-circuit current, the open-circuit voltage and the filling factor and improving the conversion efficiency.

Secondly, the method comprises the following steps: and then, executing a second graph 20 on the front surface of the silicon wafer by adopting laser, obtaining a plurality of screen layers of the fine grids 21, and simultaneously ensuring that four Mark points II 22 are symmetrically arranged in each end part in four directions, are arranged on two main grids 11 correspondingly and are arranged adjacent to the four Mark points I12 simultaneously.

The graphic structure of the Mark point one 12 and the graphic structure of the Mark point two 22 may be circular, cross-shaped, square or other regular polygon structures with any shapes, but it is required to ensure that the structures of all the Mark points one 12 in the graph one 10 are the same, and the structures of all the Mark points two 22 in the graph two 20 are the same.

The relative position between the first Mark point 12 and the second Mark point 22 is not particularly limited, as long as it is ensured that all the first Mark points 12 in the first graph 10 and all the second Mark points 22 in the second graph 20 are located on the axis of the main grid 11 in the first graph 10 and are symmetrically arranged when the second graph 20 is printed; and the circumscribed circle or the circumscribed circle of the first Mark point 12 structure in the first graph 10 and the circumscribed circle or the circumscribed circle of the second Mark point 22 structure in the second graph 20 which are adjacently arranged are arranged in a staggered clearance, and the clearance distance is not less than the sum of the radius of the circumscribed circle or the circumscribed circle of the first Mark point 12 structure in the first graph 10 and the radius of the circumscribed circle or the circumscribed circle of the second Mark point 22 structure in the second graph 20.

During printing, the width of the main gate 11 is larger than the maximum width of any Mark point, i.e. all Mark points are within the width of the main gate 11. The purpose of being arranged in the main grid 11 is to ensure easy positioning of the identification position thereof, and also to improve the appearance of the whole cell because the main grid 11 is shielded by solder strips or stacked by the stack during the assembly of the stack tiles.

Under the same conditions, the comparison values of the good product rates obtained by adopting the SE distribution printing method (in this embodiment) with the screen structure arranged concentrically (comparative example one) and the good product rates obtained by adopting the conventional common distribution printing method (comparative example two) are shown in table 1.

TABLE 1 comparison of test results

According to the upper table, adopt the utility model discloses a solar cell SE distributes printing half tone structure and printing method thereof through setting up two-layer printing half tone figure and making the position of Mark point set up for the dislocation clearance to discernment Mark point position's accuracy when guaranteeing the second time printing, with the precision that improves twice printing and stack, thereby guarantee the printing quality, improve the yields, it is that the yields improves to 98.8%.

The embodiments of the present invention have been described in detail, and the description is only for the preferred embodiments of the present invention, and should not be construed as limiting the scope of the present invention. All the equivalent changes and improvements made according to the application scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A solar cell SE distribution printing screen structure is characterized by comprising a first graph and a second graph, wherein a plurality of Mark points are respectively arranged in the first graph and the second graph, and a circumscribed circle or a circumscribed circle of the Mark point structure in the first graph which is adjacently arranged and a circumscribed circle or a circumscribed circle of the Mark point structure in the second graph are arranged in a staggered clearance manner; and the clearance distance is not less than the sum of the radius of the circumscribed circle or the circumscribed circle of the Mark point structure in the first graph and the radius of the circumscribed circle or the circumscribed circle of the Mark point structure in the second graph.

2. The solar cell SE distribution printing screen structure as claimed in claim 1, wherein the number of the Mark points in the first graph is the same as the number of the Mark points in the second graph, and the number of the Mark points is four.

3. The solar cell SE distribution printing screen structure as defined in claim 1 or 2, wherein the first pattern is a screen provided with two main grids; the second graph is a screen printing plate provided with a plurality of fine grids; the main grid and the fine grid are straight lines which are continuously arranged; and the width of the main gate is larger than the maximum width of any Mark point.

4. The solar cell SE distribution printing screen structure as claimed in claim 3, wherein the Mark points in the first graph and the Mark points in the second graph are located on an axis of the main grid and are symmetrically arranged.

5. The solar cell SE distribution printing screen structure as claimed in claim 4, wherein the Mark points near the outermost end are the Mark points in the first graph or the Mark points in the second graph.

6. The solar cell SE distribution printing screen structure as claimed in any one of claims 1 to 2 and 4 to 5, wherein the structure of the Mark points arranged in the first graph is the same as or different from the structure of the Mark points arranged in the second graph.

7. The SE distribution printing screen structure for the solar cells as claimed in claim 6, wherein the shape of the structure of all the Mark points in the first pattern is the same.

8. The SE distribution printing screen structure of the solar cell as claimed in claim 7, wherein the shape of the structure of all the Mark points in the second pattern is the same.

9. The solar cell SE distribution printing screen structure as claimed in claim 7 or 8, wherein the Mark points are structures formed by circles, crosses, squares or other regular polygons.

10. The solar cell SE distribution printing screen structure of claim 9, wherein the maximum width of all Mark dot structures is not greater than 10 mm.